The Monkey Puzzle Tree: Claimed Source Of Jet

(via Gemmology Queensland, Vol.5, No.6, June 2004)

The araucaria family (Araucariaceae) contains three remarkable genera of cone-bearing trees: Araucaria, Agathis, and Wollemia. They are tall trees native to forested regions of South America and Australia. In majestic size and beauty, they certainly rival the coniferous forests of North America and Eurasia. In fact, they are considered the southern counterpart of our northern pine forests. The type genus Araucaria is derived from ‘Arauco’, a region in central Chile where the Araucani Indians live. This is also the land of the ‘monkey puzzle’ tree (A. araucana), so named because the prickly, tangled branches would be difficult for a monkey to climb. Fossil evidence indicates that ancestral araucaria forests resembling the present day monkey puzzle date back to the age of dinosaurs. In fact, it has been suggested the tree’s armor of dagger-like leaves was designed to discourage enormous South American herbivorous dinosaurs, such as Argentinosaurus weighing and estimated 80 to 100 tons. Another ancient South American species called pino parana or parana pine (A. angustifolia) grows in southern Brazil and Argentina.

Any discussion of fossilized araucariads would be incomplete without mentioning a medieval gemstone called jet. Jet is a semi-precious gem excavated in Europe and formed by metamorphosis and anaerobic fossilization of araucaria wood buried under sediments in ancient seas. Ancestral forests that metamorphosed into jet date back to the Jurassic period, about 160 million years ago. They were similar to present day forests of monkey puzzle trees (Araucaria araucana) that grow in South America. Chemically, jet is hard, carbonized form of bituminous coal with a density similar to anthracite coal. Anthracite can be readily identified by its metallic luster. Jet takes a high polish and has been used for shiny black jewelry for thousands of years. It has a specific gravity of 1.3, almost as hard as the ironwood called lignum vitae (Guaiacum officinale). Jet became very popular during the mid 19th century England during the reign of Queen Victoria, and was often worn to ward off evil spirits and during times of mourning. In the first century AD, the Roman naturalist and writer Pliny described the magical and medicinal attributes of this beautiful mineral. The well-known analogy of ‘jet’ and ‘black’ was coined by William Shakespeare in his ‘black as jet’ from Henry VI part 2. One of the most famous areas for mining of Victorian jet is Whitby on the rugged Northeast coast of England. Although they are similar in hardness, anthracite has a metallic luster and jet is dull black. Jet takes a high polish and has been used in various carved jewelry, such as cameos and intaglios. The Victoria jet broach (circa 1890) was a popular item of jewelry during the 19th century.

Rare Diamond Goes Bright Pink In UV Light

(via Gemmology Queensland, Vol.5, No.7, July 2004/annanova.com 16/1/04)

A potentially unique diamond, which goes vivid pink when exposed to ultraviolet light, has been found in South Africa. The 13.7 carat diamond, being called the Tirisano Easter Diamond, was recovered from the Tirisano Diamond Mine in Ventersdorp diamond district of the Republic of South Africa.

Exposure to (presumably long wave) ultraviolet light causes the diamond to turn vibrant fluorescent pink. It’s not unusual for diamonds to change color in this way, but vivid pink is one of the rarest colors and the stone retains this hue for a period of time after UV exposure. Experts who have examined it so far consider it to be unique but the exact rarity of the stone will have to be established by a laboratory.

It is the property of mining companies Etruscan and Mountain Lake who plan to sell it by auction to a private collector. Les Meyer, a director of National Diamond Marketing, said, “I have had cause to view several million of stones but I have never come across a diamond of this nature, which leads me to believe that it is incredibly rare. It’s an exceptional piece due to the vibrant pink fluorescence and it has caused excitement amongst all who have examined it at National Diamond Marketing. Nobody can quite believe the color transition.”

Crystal-pulled Synthetic Chrysoberyl

(via Gemmology Queensland, Vol.1, No.2, February 2000)

According to Dr Hisashi Machida, of Japan’s Kyocera Corporation, Inamori currently produces twelve (12) synthetics for gem purposes. These man-made materials include flux-grown emerald, flocculated silica based plastic impregnated white and black opal, and synthetic alexandrite, cat’s eye alexandrite, blue sapphire, ruby, star ruby, pink sapphire, yellow sapphire, padparadscha sapphire, and green chrysoberyl which Machida claims are synthesized by a combination of a flux process and pulling.

Japan’s Kyocera Corporation has been producing gem quality Czochralski grown (crystal pulled) synthetic chrysoberyl for many years. While yellow (Fe³+ bearing), colorless, and Cr³+ containing alexandrite chrysoberyls have been available for some years, green and pink chrysoberyl have only recently been added to the product list.

The light green colored synthetic chrysoberyl is virtually inclusion-free, and is colored by V³+ of similar concentration to that found in Tunduru chrysoberyl of comparable color. Detectable quantities of Fe, Ga, and Sn were not found in the Inamori crystal-pulled synthetic chrysoberyl.
A bluish green synthetic chrysoberyl of possible Russian origin, was colored by five times the V³+ found in equivalently colored natural chrysoberyl, about 0.2 wt% Cr2O3. Like the Inamori synthetic, this green synthetic chrysoberyl had no detectable Fe, Ga, Sn.

An experimental pink synthetic chrysoberyl was colored by Ti³+ (the same chromophore that is found in hydrothermally grown pink synthetic beryl. This synthetic also was virtually inclusion free.

Identifying Synthetic Moissanite

(via Gems & Jewellery News, December 1998) Jamie Nelson writes:

If a large batch of unmounted diamonds of a range of sizes requires to be checked to determine if the batch has been salted with synthetic moissanites, then there is an easy alternative method to the methylene iodide sink or float separations.

Place the stones, table down, on the bottom of a shallow, flat bottomed, clear glass dish and cover all the stones completely with tap water. The much higher optical dispersion of moissanite (0.104 or almost x 2½ that of diamond) will reveal itself as bright spectral colored flashes, while diamonds (dispersion 0.044) will display less brightly colored sparkles. The method will still work with open-backed bracelets, necklaces and other items provided that all the stones lie table down (i.e. culet uppermost).

This being so, in the case of a finger ring mounted moissanite, the only piece of equipment needed to ensure a confident distinction is a battery-operated hand-held polariscope. The ring is placed between the polars so that the place of the stone’s table lies parallel to the optic axis of the polariscope, i.e. the long torch battery stem. The polariscope is then rotated in the axis of the torch barrel while keeping the ring stationary.

If the stone is moissanite, the usual winking of the stone’s image will be seen. If it is diamond, little or no change in the scattered light intensity will be observed. If the colorless stone happens to be another uniaxial or biaxial material, such as zircon, rutile, lithium niobate, corundum, scheelite, zincite, topaz or enstatite, then of course winking effects also will be seen. But all will be unable to pass a scratch-hardness test using the sharp edge of a carborundum (alpha silicon carbide) monocrystal applied cautiously to the girdle. However, our concern here is only to disclose the presence of moissanite and not to identify a nondiamond stone.

Synthetic Aquamarine

(via Gemmology Queensland, Vol.1, No.2, February 2000)

Tairus first produced light to dark greenish blue synthetic aquamarine in Russia in the mid-1990s. It is synthesized hydrothermally, and owes its greenish color to small amounts of Fe²+ and a Fe²+ - Fe³+ charge transfer mechanism. It is grown as flat tabular crystals on seed plates oriented at an angle to the c-axis.

Hyrothermally grown synthetic aquamarine has the following gemological properties:
Color: Light to dark greenish blue
Specific gravity: 2.65 – 2.70
Refractive index: 1.587/1.580 – 1.571/1.577
Birefringence: 0.004/0.008
Pleochroism: Weak to strong blue/colorless
Fluorescence (UV): Inert
VIS absorption spectrum: Bands at 800nm (Fe²+ ), 375nm ( Fe³+ ), shoulder at 650nm (Fe²+ - Fe³+ charge transfer, line at 400nm (Ni³+)

It can be discriminated from natural aquamarine by its:

- Chevron-like growth banding that parallels the seed plate. This growth banding which is made up of pyramidal sub-cellular growth subunits is typical of hydrothermal growth occurring of seed plates oriented at an angle to its c-axis.

- Occasional presence of flake-like aggregates of Ni-pyrrhotite and Ni-pyrite.

Chemical analysis will reveal Ni³+ as a contaminant from the walls of the autoclave in which the synthetic aquamarine was grown.

Deep Diffusion Treatment Of Corundum

(via ICA Early Warning Flash, No. 32, February 16, 1990) GIA writes:

General background
At one of the gem shows held in Tucson, Arizona, during February of 1990 one exhibitor was offering for sale blue sapphires which were reportedly enhanced with a ‘deep’ diffusion treatment. The authors of this report were shown two plastic bags of reportedly treated material, each containing an estimated several hundred carats of these treated stones. A number of these were purchased for investigation.

Gemological properties
Eleven treated stones were examined. Basic gemological properties—refractive index, birefringence, optic character, Chelsea filter reaction—were all consistent with those reported in the literature for natural blue sapphires.

The color of the stones was fairly uniform, being a medium dark slightly violetish blue. All were very transparent.

None of the stones exhibited any absorption features of the type association with iron-bearing blue sapphires. Three of the stones, however, exhibited a bright fluorescent line centered at 693nm. It is interesting in this regard that the vendor’s promotional flier states that ‘….all stones treated are genuine Ceylon sapphires…’

Key identifying features
Under longwave ultraviolet radiation all but two of the stones were inert; these same stones all fluoresced a weak to moderate, chalky yellowish green to short wave ultraviolet. The other two stones fluoresced a weak to moderate pinkish orange to longwave ultraviolet; the shortwave reaction was similar but weaker in intensity. None of the stones exhibited any phosphorescence.

Magnification and darkfield illumination revealed some features associated with corundum that has been subjected to high temperatures: diffused color banding, broken ‘dot-like’ acicular inclusions, melted included crystals resembling ‘snowballs’ with surrounding spatter halos, and superficial sintering in surface pits. It should be noted that these features were, in general, minor.

Examination using diffused transmitted light without immersion or magnification showed color concentrations along facet junctions and outlining of the girdle edge. Also noted was some variation in color from one facet to another.

Using immersion and diffused transmitted light without magnification the color concentrations along facet junctions and the girdle as well as the uneven facet-to-facet coloration were again noted. In many cases these features were significantly more obvious when immersion was now used.

Suggestion
Diffusion treated sapphires are now being made increasingly available in the market. It this becomes important to use diffused transmitted illumination and immersion in the routine examination of corundum.

The Shawshank Redemption

Memorable quote (s) from the movie:

Andy Dufresne (Tim Robbins): You know what the Mexicans say about the Pacific?

Red (Morgan Freeman): No.

Andy Dufresne (Tim Robbins): They say it has no memory. That's where I want to live the rest of my life. A warm place with no memory.

Hardness Testing Of Gemstones: A Re-evaluation Of The Values

(via Gemmology Queensland, Vol 3, No.1, Jan 2002/IGC Conference Madrid 2001) Michael Gray writes:

Hardness testing is one of the methods that a mineralogist uses to determine the identity of a mineral sample, but which has rarely been used by the gemologist. A mineralogist can usually find some inconspicuous face or broken area to conduct a scratch test, but the gemologist rarely has had a surface on a gemstone to do a comparable test without visible damage to the polish of the stone. However, the ability to choose a random surface may give a false value when a range of hardness exist, as in the case of kyanite, which has a documented variation from 4.5 to 5 on the Moh’s scale of hardness. While a species with such a diverse range can be easy to identify and test, there are many other species that have smaller variations that have not been measured. We are preparing a method of testing hardness during the faceting process. Our present system was developed by Friedrich Mohs in 1822, whereby he set relative values of hardness to ten easily obtainable species for comparison to each other, and measured by making scratches on surfaces of the unknown material with these ten species. This scale is still used as the standard, but variations in hardness has been known since at least 1844 using a device called sclerometer, and researchers were able to deduce objective values, although some variations in these scales are noted, depending upon the method and preparation used. In fact, some researchers determined that topaz is less hard than quartz when the sclerometer was used on powders of these two species.

Lapidaries have always noticed some of these variations in hardness in some species, especially noticeable in heat treated sapphires and rubies. A good example of this variation is the species fresnoite. In the references, the published hardness varies from “3 to 4” to a value of 4.7. A lapidary must rely upon these figures to determine which cutting and polishing laps and media to use in fashioning a gemstone. A great variation in hardness was noticed in the grinding and polishing of the stone, with only one direction being noticeably ‘soft’ as compared to the other facets. There is only one direction being in the range of 4 in hardness, with all other directions being noticeably harder.

These are hardly the only examples to cite; there are many materials, such as spodumene, sillimanite, elbaite, and many of the garnets that exhibit some noticeable variation in hardness during faceting. Diamond cutters know of the variations in their specialty, and use that knowledge in the fashioning of those gems.

The argument could be made that Moh’s scale has worked for almost two centuries, and that there is n need to change this system. That is not the purpose of this study. There are a number of purposes why this study has been initiated to determine the actual hardness of a species, such as fresnoite, where the original description may be inaccurate to document the variation of hardness, as well ad ‘normal’ hardness, within a species. To determine if a variation of hardness may be caused by a man-induced treatment, such as heat treatment of corundum, which then can be used as a way of detecting these treatments. This might also be taken further to determine origin, as well, depending upon impurities, coloring agents, and variations in chemical composition to help clear up conflicting values in different publications to relate these values to the existing Moh’s scale of hardness so that the numbers are understandable to academics and lay persons alike.

Equipment has been developed recently that makes it much easier to conduct hardness testing. The development of ultrasonic indenters that can be calibrated based on the Rockwell and Vickers scales, two of the glass and metal industry’s standards, should eliminate most of the danger of stone breakage during hardness testing. Our testing will be done during the cutting stages, so any noticeable marks made on the softer stones can be polished out.

The ten species used in the Moh’s scale will have been measured, resulting in a set of numbers that will set the parameters for the decimal places between species. Stones are being faceted of these materials to make note of any noticeable variations during cutting, and then measurements taken of these materials. After these values are established, checked, and documented, other species will be faceted, with noticeable hard and soft areas marked for testing. On stones with variable hardnesses, at least four hardness tests will be performed, one each on the ‘softest’ and ‘hardest’ directions, since these normally occur only in one direction, and several tests to establish the ‘normal’ hardness, the hardness over the rest of the material. Therefore, while a range may be established, a third number may represent the general hardness of the material.

The practicality of using gemstones for hardness testing is the general ‘purity’ of the sample being used. Many of the published hardness values were obtained using tiny pieces of the type specimens when they were first discovered and therefore were probably unable to get much accuracy, especially minerals described prior to the 1960s. Unfortunately, once a mineral is named and documented, the values may come up dependent upon the locality and/or if the material has been treated, and all of this information will be documented, as well, whenever possible. Ultimately, we should be able to document the crystal orientation that these variable hardnesses will occur.

There is also an important side benefit to this testing. While hardness testing is only used in a miniscule number of gem identifications, we hope to show that this test can be used in gem labs, using the modern equipment available today. The marks made by a skilled and knowledgeable worker using this modern equipment can be so tiny as to be undetectable by the naked eye, and can be placed on an inconspicuous spot on the girdle or pavilion of the stone. With the values obtained through this research, there will be one more test available for questionable gems. It should also be possible to test mounted stones as well, where refractive indices and specific gravities may not be able to be obtained without removal of the stone from the mounting.

Elements Of Physical Geology

By James H Zumberge & Clemens A Nelson
John Wiley & Sons, Inc
1976 ISBN 0-471-98674-7

James H Zumberge & Clemens A Nelson writes:

This book is a direct outgrowth of our Elements of Geology, Third Edition. It is intended for a one-term course in physical geology for the nonmajor. Because we think that a historical perspective is essential to the understanding of earth science, a number of items commonly reserved for books on earth history are included in Chapter 6, Geologic Time. To provide for an appreciation of geologic time in the earlier chapters, the geologic time scale is introduced in the first chapter.

Although many recent text have used the exciting developments in sea floor spreading and place tectonics as a theme around which to organize the subject matter of physical geology, we have preferred the more traditional approach for pedagogic reasons. We believe that an investigation of the earth from the inside out provides a better basis on which student can begin to understand his environment. Thus, the first nine chapters deal with the fundamental materials of the earth and its internal characteristics and processes; the following seven chapters deal with processes that have shaped the surface of the earth and provided its infinite variety of topographic forms.

It is also common practice for current texts to devote a single unit to Environmental Geology. We believe that geology has always been a fundamental environmental science and that the subject of the environment, including geologic hazards, is better served by its inclusion in the chapters where it is natural part of the subject under discussion. Thus, the reader will find environmental problems treated in the chapters on volcanoes, earthquakes, climate, landslides, groundwater, rivers, wind, glaciers, oceans, and resources.

The text of most chapters from Elements of Geology has been revised, and new illustrations have been added. The materials can structures of the crust of the earth are treated in chapter 3, Materials of the Earth’s Crust, and chapter 4, Structures of the Earth’s Crust. These subjects were incorporated into a single chapter in Elements of Geology. Chapter 9, Global Tectonics and Mountain Building, has been revised and expanded and includes a historical account of mountain building theories and a detailed account of the new revolution in geology—that of sea floor spreading and plate tectonics. In each of the chapters dealing with surface processes (chapters 10 to 16), examples from the geologic record have been included to illustrate the uniformitarian relationships between present observations and the past record of the earth.

Chapter 17, Resources from the Earth, is new; it incorporates a number of separate discussions from Elements of Geology and current problems of environmental geology and mineral and energy resources.

We are grateful to the people who supplied photographs for this book. We particularly thank Tad Nichols of Tucson, Arizona, for providing many outstanding photographs of geologic features and phenomena. Sources are given for all photographic illustrations except the ones taken by us. We also thank the National Geographic Society for permission to use parts of their colored maps of the Atlantic and Pacific Ocean floors, which appear as Plates V and VI, preceding Chapter 9. Again we thank Derwin Bell of the Department of Geology at the University of Michigan whose excellent illustrations from Elements of Geology have served so well. We also thank Jeanie Martinez of the Department of Geology, University of California, Los Angeles, for several additional illustrations, and Kathyryn Brown at the University of California, Los Angeles, for help in manuscript preparation.

A great many people have made general and specific contributions in the preparation of the book. Our colleagues in the College of Earth Sciences at the University of Arizona, the Department of Geology, University of Nebraska, and the Department of Geology, University of California, Los Angeles, have been especially generous of their expertise. Don Deneck of Wiley has been both a spur and helpful associate during the many stages of preparation. We express our gratitude to our wives, Marilyn Zumberge and Ruth Nelson, for their patience and understanding while this book was being written.

The Founders Of Geology

By Sir Andrew Geikie
Dover Publications, Inc
1962

Dover Publication writes:

The later half of the 19th century and the first two decades of the 20th century are especially interesting to students of geology, for it was during those seventy years that the main modern foundations of the science were laid. This book surveys the high moments and central figures in that era of seminal geological activity.

It recounts the story of the progress of geological ideas by reviewing the careers of some of the leaders by whom the progress was chiefly effected, giving full consideration to the lives and work of these major figures, and indicating in the process how geological ideas arose and were slowly worked out into the forms which they now wear. Some of the men whose careers and contributions are examined are Palissy, Guettard, Desmarest, Pallas, De Saussure, Arduino, Lehman, Fuchsel, Werner, Hutton, Playfair, Sir James Hall, Giraud-Soulavie, Cuvier, Michell, Lyell, Logan, Darwin, Agassiz, Nicol, and others.

The author discusses such matters as geological ideas among the Greeks and Romans; growth of geological ideas in the Middle Ages; scientific cosmogonists—Descartes and Leibnitz; the rise of geology in France; the foundation of volcanic geology; the rise of geological travel; the history of the doctrine of geological succession; the Wernerian school of geology; the rise of the modern conception of the theory of the earth; the birth of experimental geology; the rise of stratigraphical geology and paleontology; early teachers and textbooks; the transition or Greywacke formation resolved into the Cambrian, Silurian and Devonian systems; the primordial fauna of Barrande; the pre-Cambrian rocks first begun to be set in order; the influence of Darwin; adoption of zonal stratigraphy of fossiliferous rocks; the rise of glacial geology; the development of geological map-making in Europe and North America; the rise of petrographical geology; and other related topics.

Manufacturing, Production, And Trade Of Synthetic And Enhanced Gems In Modern Russia

(via Gemmology Queensland, Vol 3, No.1, Jan 2002/IGC Conference Madrid 2001) Vladimir S Balitsky writes:

Synthetic gems
In modern Russia in industrial scales practically all kinds and varieties of synthetic analogues of natural gems are produced as well as it was in former USSR. Moreover, crystals of the whole row of compounds having no analogues in nature but possessing properties of gems are synthesized. A list of all synthetic gems produced at present in Russia is given in Table 1 with methods of their obtaining approximate volumes of production and their prices. As can be seen, leuco-sapphire, ruby and sapphires are produced in large quantities. They are grown mainly from the melt by the methods of Verneuil, Czochralski, Kyropulus and Zone melting. Lately they have been grown in small quantities by hydrothermal and flux methods. Traditional Russian synthetic gems also include quartz and its colored varieties especially amethyst, citrine, blue and green quartz. Lately they have developed new technologies of producing two colored amethyst-citrine quartz (ametrine), pink transparent phosphorous-bearing quartz and unusual copper-bearing aventurine in small quantities. Under artificial conditions drusses of both colorless and colored quartz are also grown.

Table 1
Synthetic gems produced in Russia at present

Name: Alexandrite
Growth technique: Czochralski
Approximate production/kg per year: up to one hundred
Approximate price of raw material (US$/per kg): 1000 – 7500

Name: Alexandrite
Growth technique: Flux
Approximate production/kg per year: a few kg’s
Approximate price of raw material (US$/per kg): 1000 – 7500

Name: Amethyst
Growth technique: Hydrothermal
Approximate production/kg per year: a few thousand
Approximate price of raw material (US$/per kg): 50 – 150

Name: Ametrine
Growth technique: Hydrothermal
Approximate production/kg per year: a few hundred
Approximate price of raw material (US$/per kg): 100 - 150

Name: Aquamarine
Growth technique: Hydrothermal/Flux
Approximate production/kg per year: a few
Approximate price of raw material (US$/per kg): 3000 – 5000

Name: Cubic Zirconium Oxide (CZ)
Growth technique: Skull Melting
Approximate production/kg per year: a few thousand
Approximate price of raw material (US$/per kg): 30 – 60

Name: Diamond
Growth technique: HPHT
Approximate production/kg per year: up to 2
Approximate price of raw material (US$/per kg): 1000000

Name: Emerald
Growth technique: Hydrothermal / Flux
Approximate production/kg per year: up to 50
Approximate price of raw material (US$/per kg): 5000 – 7500

Name: Emerald Drusses
Growth technique: Flux
Approximate production/kg per year: a few
Approximate price of raw material (US$/per kg): 1000 – 15000

Name: Forsterite
Growth technique: Czochralski
Approximate production/kg per year: a few
Approximate price of raw material (US$/per kg): 5000

Name: Gadolium Gallium Garnet (GGG)
Growth technique: Czochralski
Approximate production/kg per year: a few dozen
Approximate price of raw material (US$/per kg): 10000

Name: Leuco sapphire
Growth technique: Czochralski
Approximate production/kg per year: a few thousand
Approximate price of raw material (US$/per kg): 350 - 400

Name: Leuco sapphire
Growth technique: Vernueil
Approximate production/kg per year: a few thousand
Approximate price of raw material (US$/per kg): 250 – 300

Name: Leuco sapphire
Growth technique: Kyropulus
Approximate production/kg per year: a few thousand
Approximate price of raw material (US$/per kg): 350 - 400

Name: Leuco sapphire
Growth technique: Horizontal Zoning Melt
Approximate production/kg per year: a few thousand
Approximate price of raw material (US$/per kg): 400 – 500

Name: Morganite
Growth technique: Hydrothermal / Flux
Approximate production/kg per year: a few
Approximate price of raw material (US$/per kg): 3000 – 7000

Name: Malachite
Growth technique: Chemical precipitation from aqueous solutions
Approximate production/kg per year: up to thousand
Approximate price of raw material (US$/per kg): 40 -70

Name: Moissanite
Growth technique: High pressure sublimation
Approximate production/kg per year: a few dozen
Approximate price of raw material (US$/per kg): 25000 – 50000

Name: Opal noble
Growth technique: Chemical precipitation + impregnation by plastic or zirconium hydroxide or silica + high temperature treatment
Approximate production/kg per year: a few dozen
Approximate price of raw material (US$/per kg): 20000 – 35000

Name: Quartz colorless
Growth technique: Hydrothermal
Approximate production/kg per year: a few hundreds of thousands
Approximate price of raw material (US$/per kg): 40 – 600

Name: Quartz colored (yellow, green, blue, brown, smoky, milky)
Growth technique: Hydrothermal
Approximate production/kg per year: a few hundreds of thousands
Approximate price of raw material (US$/per kg): 40 – 80

Name: Quartz pink (transparent)
Growth technique: Hydrothermal
Approximate production/kg per year: a few dozens
Approximate price of raw material (US$/per kg): 3000 - 5000

Name: Quartz drusses
Growth technique: Hydrothermal
Approximate production/kg per year: a few dozens
Approximate price of raw material (US$/per kg): 50 – 100

Name: Ruby
Growth technique: Vernueil / Czochralski / Horizontal Zoning Melt
Approximate production/kg per year: a few thousands
Approximate price of raw material (US$/per kg): 250 – 1000

Name: Ruby
Growth technique: Hydrothermal
Approximate production/kg per year: a few
Approximate price of raw material (US$/per kg): 5000 - 10000

Name: Sapphire
Growth technique: Verneuil / Czochralski
Approximate production/kg per year: a few thousands
Approximate price of raw material (US$/per kg): 250 – 1000

Name: Sapphire
Growth technique: Hydrothermal
Approximate production/kg per year: a few
Approximate price of raw material (US$/per kg): 5000 – 10000

Name: Spinel
Growth technique: Flux
Approximate production/kg per year: a few
Approximate price of raw material (US$/per kg): 25000

Name: Spinel drusses
Growth technique: Flux
Approximate production/kg per year: a few
Approximate price of raw material (US$/per kg): 25000

Name: Turquoise
Growth technique: Chemical precipitation + high pressure treatment
Approximate production/kg per year: a few hundreds
Approximate price of raw material (US$/per kg): 50 – 80

Name: Yttrium Aluminum Garnet (YAG) (Colorless and colored)
Growth technique: Czochralski / Horizontal Zone Melting
Approximate production/kg per year: a few thousands
Approximate price of raw material (US$/per kg): 400 – 700

Name: Zincate
Growth technique: Hydrothermal
Approximate production/kg per year: a few
Approximate price of raw material (US$/per kg): 30000

An essential role in the production of synthetic gems in modern Russia belongs to emerald. It is mainly grown under hydrothermal conditions, but in small quantities it is obtained from flux. Besides emerald, other colored varieties of beryl are grown in very limited quantities. Among other popular synthetic gems grown in Russia, one should notice alexandrite and spinel. First, it was grown by Czochralski and flux methods, and then by Verneuil and flux. The most precious of them are crystals grown from flux. Among other synthetic gems, refined black and white noble opal is also produced. The material may look very similar to the natural opal. Synthetic malachite has also been produced successfully. A considerable progress has been made in the synthesis of large diamonds (yellow, blue and colorless) with the maximum weight up to 5 ct. Within the last two years synthetic moissanite has also been produced. However both synthetic diamonds and synthetic moissanites are produced in rather restricted quantities.

Enhanced gems
Many gems found and imported into Russia (corundum, topaz, quartz, garnet, danburite, scapolite, beryl, tourmaline, turquoise, coral, charoite, lazurite, agates etc.) are of low quality. The gems are often subjected to enhancement with the purpose of increasing their quality. Table 2 gives a list of stones with indicative treatments.

Name: Agate (chalcedony)
Enhancement process: impregnation / heat treatment / irradiation
Enhancement effect: pale colors to yellow, brown, green, blue, black and red; pale colors to brown and red; change of color to dark gray.

Name: Amazonite
Enhancement process: heat treatment / dyeing
Enhancement effect: improvement of color

Name: Amber
Enhancement process: reconstruction / heat treatment / pressing
Enhancement effect: augmentation of weight; improvement of inner structure with induced cracking; augmentation of weight

Name: Charoite
Enhancement process: dyeing
Enhancement effect: improvement of color

Name: Corundum (colorless and colored)
Enhancement process: heat treatment / heat treatment with diffusion / surface coating
Enhancement effect: colorless and pale colors to blue

Name: Danburite
Enhancement process: irradiation / heat treatment
Enhancement effect: remove colorless to brownish—pink / fading

Name: Heliodor
Enhancement process: heat treatment
Enhancement effect: remove yellow to blue (aquamarine)

Name: Lazurite
Enhancement process: impregnation / heat treatment
Enhancement effect: improvement of color

Name: Nephrite
Enhancement process: hydrothermal treatment / irradiation
Enhancement effect: lightening of dark green color to white / darkening of green and brown to black

Name: Quartz
Enhancement process: heat treatment / irradiation / surface coating
Enhancement effect: dark smoky to pale smoky or greenish yellow or colorless / colorless and pale colors to smoky or greenish yellow / colorless and pale colors to pink or blue

Name: Radonite
Enhancement process: dyeing
Enhancement effect: improvement of color

Name: Topaz
Enhancement process: irradiation / irradiation + heat treatment
Enhancement effect: colorless and pale colors to yellow brown or reddish brown / colorless or brown to brownish green or blue / brown or orange to pink / brown or green or blue to colorless

Name: Turquoise
Enhancement process: impregnation under high temperature and high pressure
Enhancement effect: improvement of color / rise of hardness

Tootsie

Memorable quote (s) from the movie:

Michael Dorsey (Dustin Hoffman): Are you saying that nobody in New York will work with me?

George Fields (Sydney Pollack): No, no, that's too limited... nobody in Hollywood wants to work with you either. I can't even send you up for a commercial. You played a tomato for 30 seconds - they went a half a day over schedule because you wouldn't sit down.

Michael Dorsey (Dustin Hoffman): Yes - it wasn't logical.

George Fields (Sydney Pollack): You were a tomato. A tomato doesn't have logic. A tomato can't move.

Michael Dorsey (Dustin Hoffman): That's what I said. So if he can't move, how's he gonna sit down, George? I was a stand-up tomato: a juicy, sexy, beefsteak tomato. Nobody does vegetables like me. I did an evening of vegetables off-Broadway. I did the best tomato, the best cucumber... I did an endive salad that knocked the critics on their ass.

Natural And HPHT-annealed Pink And Blue Diamonds

(via Gemmology Queensland, Vol 3, No.1, Jan 2002/IGC Conference Madrid 2001) George Bosshart writes:

The Gubelin Gem Lab engaged in a new study of HPHT-annealed specimens in order to elaborate criteria for the separation of the fancy diamond colors produced by the General Electric Company from the natural pink and blue colors. The key characteristics of the natural colors are briefly outlined and first indicators for HPHT treatment detection are given below.

Natural pink colors exist in both type Ia and type IIa diamond but exhibit a wider color variety in the first group. Type Ia diamond is found in pure pink to red to purple hues but pink and red are more frequently combined with orange and brown color modifiers. Type IIa diamond is limited to light pink to pink hues which may be modified by secondary orange or brown colors. Red hues do not occur in this group but purple does, as a rare and subordinate modifier at least.

In our natural pink study group of over 100 gem quality diamonds, 75% belonged to type Ia, 2% to the mixed type IbIaA, and 22% to type IIa (of which 15% revealed nitrogen-free infrared survey spectra, whereas 7% showed trace amounts of nitrogen as A or B aggregates or as single nitrogen).

In pink type Ia diamond in particular, an irregular color lamination and patchiness can frequently be observed under magnification. These obvious disturbances are plausibly interpreted as being caused by internal plastic deformation which itself is a reaction of the diamond structure to the impact of geotectonic shear stress (active during orogenetic phases), thus avoiding breakage. However, the cause for the pink color center, a wideband absorption centered at 560nm (2.2 eV), is not known in detail.

The strength of the 560nm absorption band determines the intensity of the type Ia pink color. Pink changes to red or purple when this band reaches higher amplitudes (with absorption coefficients in the order of 0.6 cm¯¹ and above). Nitrogen contents in the form of A and/or B aggregates vary in natural pink diamond from extremely small (in type IIa) to extremely large. In type Ia diamond, hydrogen may be present as well, however, in minor to moderate amounts only. Type IIa diamond features the same 560 nm absorption system and an identical but limited intensity relationship (mentioned above). It follows that neither nitrogen nor hydrogen impurities cause the pink color.

In pink diamond, a slight increase of the general absorption in the blue to violet regions of the spectrum results in an orange color modifier which in turn may alter to a brown modifier when the underlying absorption rises more strongly. This absorption is caused by another, equally unknown type of structural defect in the diamond crystal lattice.

In addition to the above color centers, N3 and H3 absorption in type Ia diamond may add a yellowish to orangy modifier component when present in some strength. This combination is typically encountered in Argyle and Brazilian brownish to purplish pink and red diamond. A rarely occurring 480nm absorption band adds a pure orange component to pink diamond colors.

Natural blue diamond varies less than in hue than pink color group. The only modifier of importance is gray. Natural blue occurs in type IIb diamond exclusively (rare specimens being gray violet rather than blue and belonging to hydrogen-rich type IaB). Type IIb diamond is an electric semiconductor due to the substitution of carbon atoms by ppb amounts of boron on the lattice sites of diamond.

The absorption diagram of blue diamond is characterized by a unique mid-infrared absorption superimposed n the inherent diamond absorption in the two-phonon region, with lesser absorption in the adjacent one and three phonon areas. The strongest absorption band is situated at 2802 wavenumbers. It is also typical for blue diamond that the absorption level steadily decreases from the mid-infrared through the near-infrared and visible regions into the ultraviolet part of the electromagnetic spectrum without showing any absorption bands. The absorption minima of blue diamonds fluctuate from 240nm at the base of the fundamental absorption edge to about 500nm. This variation does have an influence on the exact hue of the blue colors which may range from violetish to slightly greenish blue. The dominant wavelengths, as determined by colorimetric measurement, lie in the 465 to 495nm region and confirm that the primary hue is blue. Only one specimen was encountered so far with a dominant wavelength of 435nm corresponding to a violet-blue hue.

The hues of type IIb diamonds frequently are not easy to determine visually due to their weak color saturations and relatively high tones. The type IIb infrared absorption, e.g. the 2802 wn band, could serve as an indicator for the saturation of blue since it is related to the boron content. However, the absorption coefficient of this and other MIR absorption bands for some reason does not appear to be straightforward measure of the blue saturation of type IIb diamond. When the general absorption in type IIb diamond rises to higher levels, and this is particularly important in the visible part of the spectrum, the color impression shifts to bluish gray and even to neutral gray colors (44% of the blue group of 75 specimens grade blue, 40% mixed blue to gray, 8% neutral gray and 1% violet blue).

There is a small proportion (7%) of type IIb diamonds which possesses an increased absorption in the entire ultraviolet region. Accordingly their absorption minimum is more pronounced than in the pure blue colors and shifts into the center of the visible region, with dominant wavelengths ranging from about 500 to slightly over 600nm. Such diamonds essentially appear gray with a greenish to yellowish color modifier. It is interesting to note that greenish gray and yellowish gray colors also occur in type Ia diamond, showing high B nitrogen aggregate and high hydrogen contents, respectively high A aggregate and H contents.

The presence of gray color modifier in type IIb blue diamond may be interpreted as a color generated by the combination of boron with single nitrogen or other chemical impurities and/or by structural defects. However, gray color may also be independent of boron traces at all. A very weak 270 nm band was encountered in several natural blue diamonds and is allocated to single nitrogen.

HPHT Pink and Blue
Prior to 1999, it may have appeared inconceivable that natural off-color diamonds could be improved to obtain the best colors known (D to H color grades), i.e. colorlessness. However, the General Electric Company successfully achieved this breakthrough by applying a modified version of the high pressure/high temperature technology used to grow synthetic diamonds. Since the turn of the millennium, GE has been marketing these virtually colorless diamonds predominantly on the American market and under the brand name, Bellataire (formerly GE POL).

Fancy pink and blue diamond colors are described ad desirable as the white ones. As a consequence, the production of pink and blue became the second great challenge and in 2000. GE managed to add convincing pink and blue color replicas to the wide range of already existing treated diamond colors. In contrast to those irradiated and annealed pink to purple and irradiated blue to green diamond colors, General Electric’s latest products look entirely natural. The exact starting material and its abundance will not be made public by GE. However, experience gained in our study of GE POL diamonds before and after HPHT-annealing (Smith et. al 2000) tells us that the potentially improvable diamond rough must be restricted to type IIa brown respectively type IIB gray to brown specimens of fairly high clarity grades. This implies that the number of diamonds HPHT-annealable to pink and blue colors is considerably inferior to that of the colorless type IIa specimens and that most of the enhanced fancy colors may be low in intensity. A preliminary sampling consisted of six (0.14 to 8.55 ct) pink and two (0.21 and 0.27 ct) blue diamonds HPHT-annealed by GE. The pink stones investigated evidenced that only type IIa and near-type IIa diamonds had been selected. Colorimetric data showed that the resulting pink and blue hues are well within the range of their natural type IIa resp. IIb counterparts. Red or strong blue colors were not observed in this batch, but it included light to intense pink to purple pink colors plus one faint blue and one medium blue specimen each. Brown resp. gray modifiers were subordinate. At this moment, it is safe to state that, comparable to colorless Bellataire diamonds, gemological standard methods (microscopy, UV fluorescence etc.) will not permit a safe separation of natural and HPHT-annealed type IIa pink and semi-conductive blue diamonds. The mid-infrared and UV/VIS spectra of five (out of six) pink samples revealed nitrogen (A or B aggregates, N3 and N9 centers), however, in trace amounts only. The spectra of the blue specimens were very similar to those of the natural colors as well.

Among the optical techniques, Raman photo-luminescence with He/Cd and an Arion laser offer the most promising results. The color enhanced diamonds showed a smaller number of PL bands than recorded for natural colors and the intensities of the bands also differed noticeably. As an example, the 575nm and 637nm bands of the Nº and N centers respectively were definitely stronger than in natural pink diamonds. More and improved criteria are to be expected for both color groups from a larger data base. Advanced testing methods such as X-ray topography or cathodoluminescence applied during our former investigation of eleven colorless diamonds before and after HPHT processing by GE were not used for reasons of limited time and absence of diamonds selected to be processed.

What can be expected as the ultimate achievements in color enhancement by HPHT-annealing?
Cape series diamond becoming colorless and brown resp. gray diamond adopting other colors than colorless, pink or blue.

The Five Ages Of A Lecturer

(via Wahroongai News, Volume 31, Number 3, March 1997)

In How Professors Develop as Teachers, Peter Kugel (TLDU Talk, Issue No.3, July 1996—Teaching and Learning Development Unit, University of Waikato quoting Peter Kugel’s (1993) How Professors Develop as teachers, studies in Higher Education) suggests five distinct stages in the development of a teacher in higher education, and the transitions between each of these stages.

Stage 1: Focus on self
At the start of their teaching career, Kugel suggests, lecturers are mainly concerned with themselves, and more specifically with their survival in front of their first few classes.

Transition 1—self to subject. Once they know they can survive, and even start to feel good about their teachings, their focus shifts rapidly to the subject matter.

Stage 2: Focus on subject
Here the lecturer rediscovers their enthusiasm for their subject, and works hard to extend their knowledge further and then to share it all with their students.

Transition 2—subject to student. After a while, the lecturer may start to notice that students are not learning all that the lecturer is teaching, and may not all share the lecturer’s enthusiasm. Why might this be?

Stage 3: Focus on student
The lecturer sees how greatly students differ one another—in approach to learning, in interest, in motivation, in competence. The lecturer starts to adopt a wider variety of approaches to engage the heterogeneous body of students before them. The lecturer’s interest shift from ‘what am I saying?’ to ‘what are they hearing?’

Transition 3—students as receiver to student as active learner. Even when focusing on the students, the lecturer was still concentrating on what she or he was doing to the students rather than on what the students were doing. The lecturer is now finding limits to what this can achieve.

Stage 4: Focus on student learning
The lecturer increasingly devises appropriate student activities and opportunities for learning.

Transition 4—student as active learner to student as independent learner. The more actively the students engage with their work, the more responsibility they take for their own and each other’s learning.

Stage 5: Focus on the student as an independent learner
When the student truly knows how to learn for her or himself, the lecturer’s work with that student is successfully complete.

Body Jewellery

By Donald Willcox
Sir Isaac Pitman and Sons Ltd
1974 ISBN 0-273-00723-8

Sir Isaac Pitman and Sons writes:

Essentially a pictorial survey of the best in international jewellery design today, Body Jewellery is made up of essays by those designers who have contributed pieces of work to the photographic section.

The designers range from the world famous to less well-known but successful beginners. Donald Willcox provides the summarizing introduction. A variety of topics are covered: from technical aspects of jewellery work to general views on the way jewellery design is developing or ought to develop. The writers all share a determination to break away from the confining tradition of gold and silver jewellery for the ears, wrist, neck and fingers, and to incorporate instead more of the artist’s imagination in ornaments for virtually any part of the body, made out of more or less any malleable material.

Jewellery craftsmen will find ideas and encouragement here. With over 400 illustrations, it is a valuable book for art students and a useful reference for designers.

Donald Willcox describes himself as an ‘author, lunatic, poet, craftsmen, critic and educator..’. He is the author of three poetry books and many on design and crafts, including Leather, which is also published by Pitman. His articles have been widely published in such magazines as Craft Horizons and American Artist.

Synthetic Corundum

(via Wahroongai News, Volume 23, Number 2, February 1989)

The natural growth angle (angle to the c-axis on which the atoms of Al2O3 will stack) of the Verneuil corundum boule is 60°.

Boules grown on seeds cut at 90° to the c-axis have square cross sections.

Boules grown on seeds cut at 0° to the c-axis fracture readily…..both during growth, and during cooling or subsequent cutting.

It is not possible to cut or shape any Verneuil corundum boules until they have been adequately annealed to remove stresses induced during their growth.

Impurities of materials, bubbles, included unmelted powder particles, poor dissemination of the chromophore, and an unclean vertical blowtorch—all contribute to the production of poor quality boules.

The Lost Weekend

Memorable quote (s) from the movie:

Don Birnam (Ray Milland): It shrinks my liver, doesn't it, Nat? It pickles my kidneys, yeah. But what it does to the mind? It tosses the sandbags overboard so the balloon can soar. Suddenly I'm above the ordinary. I'm competent. I'm walking a tightrope over Niagara Falls. I'm one of the great ones. I'm Michaelangelo, molding the beard of Moses. I'm Van Gogh painting pure sunlight. I'm Horowitz, playing the Emperor Concerto. I'm John Barrymore before movies got him by the throat. I'm Jesse James and his two brothers, all three of them. I'm W. Shakespeare. And out there it's not Third Avenue any longer, it's the Nile. Nat, it's the Nile and down it moves the barge of Cleopatra.

(New) Russian Tanzanite Imitation

Jewellery News Asia (August, 1999) writes:

A visually effective tanzanite imitation of Russian manufacture has entered the marketplace. This imitation is potentially confusing as it displays greenish blue to purplish pink directional pleochroism. Investigations by Shane McClure of GIA’s Gem Trade Lab in New York have revealed that this imitation is a synthetic forsterite (magnesium silicate)…..the magnesian end member of the forsterite-fayalite solid solution series of which the gemstone peridot is an intermediate member.

According to McClure the presence of scattered ‘pinpoints’ and small ‘needles’ suggest that this man-made material has been synthesized by the crystal pulling (Czochralski) technique. This imitation which is doped by cobalt, and therefore should display Co absorption spectrum and fluoresces red under LWUV and the Chelsea filter; specific gravity is 3.42 and refractive index is 1.635-1.670.

American Freshwater Pearls

(via Wahroongai News, Volume 33, No.8, August 1999)

The freshwater mussels of the rivers and lakes of North America produce a surprising range of both natural and cultural pearls.

Natural pearls
North American Indians, who lived along the rivers and lakes of North America, made use of indigenous freshwater mussels both as a source of food and as a valued source of pearls for ornamental purposes. By the mid 16th century Spanish explorers also had become aware of and greatly appreciated this source of natural pearls.

Following the mid-19th century discovery of pearls in Notch Brook near Paterson, New Jersey, an active trade in these pearls and their shells began in North America. This trade exploded some decades later as pearl shelling also developed along the rivers of Ohio, Wisconsin, Tennessee, and Arkansas. By the end of World War II these fisheries were no longer economically viable, as plastic has supplanted pearl shell for the manufacture of buttons. The pearl shelling industry of North America revived during the early 1950, when Japanese demand for shells for the manufacture of bead nuclei suitable implanting into Akoya oysters became paramount. Today, natural pearls are still recovered from these rivers and lakes; but only as a by-product of the pearl shelling industry.

Many species of bivalve freshwater mollusk, belonging to the family Unionidae, inhabit the sandy-gravely bottoms of fast flowing rivers, and to a lesser extent the more muddy bottoms of gravely lakes of the Mississippi and its tributaries. However, over the last century damming these rivers, increased silting from agriculture and strip mining, and the introduction of competitive predators such the zebra mussel have decimated the native mussel population of North America. Today hardy survivors such as the pigtoe (Pleerobema cordatum) maple leaf (Quadrula quadrula), three ridge (Amblema costata), and washboard (Megiaonaias gigantean) are still surviving with some difficulty.

Natural pearl form as a result of small pieces of mantle tissue dislodged from mussels by the bites of predatory fish, by invasion of the mussel’s body tissues by boring parasites, or by the accidental implantation of fragments of shell or fish scales into mantle tissues. The shape of pearls obtained from these freshwater mussels varies with where they grow within the mussel. For example, round pearls form in or around the posterior adductor muscle, adjacent beak area, or the body of the mollusk. It is hypothesized that the opening and closing of valves of the mussel rotates the forming pearl thus producing an even distribution of nacre. Elongated symmetrical shapes of pearl form between the adductor muscle and the hinge: with ridged barrels probably resulting from the forming pearl rotating against a projection from the hinge. Button shaped pearls and turtle backs (with flattish bottoms) are found near the outer lips of the valves. Flattish teardrop shaped ‘wings’ form in the posterior hinge area, while more angular chunky pearls form in the anterior hinge area. Rare bumpy rosebud pearls either form in the beak area or deep within the body of the mussel. Colors of natural pearls range from common white to attractive pastel shades of pink, rose, lavender and purple. The lusters of these pearls vary widely. Major factors controlling the color and luster of these freshwater pearls include the distribution of color across the shell of various species of mussel, location of the pearl in the mussel, the health of the mussel, and water and environmental conditions under which the pearl grew.

Cultured pearls
In the early 1960s the Tennessee Shell Company—the major supplier of freshwater shell for the manufacture of beads for the Japanese Akoya industry—began experiments in the culture of freshwater pearls in a man-made TVA lake near Lexington, Tennessee. These experiments were initiated by John Latendresse and his Japanese-born wife. Twenty years later and with the assistance of available Japanese freshwater pearl cultivating technology, pearl culture farms had been set up and were operating economically in several unpolluted lakes leased from TVA.

American cultured pearls are produced in the following sequence, based on basic Lake Biwa technology:

- Individual hookah-equipped divers collect mature mother mussels from the Mississippi River and its tributaries; care being taken that younger mussels are left to continue breeding.
- The harvested mussels are placed into pockets of ‘kangaroo’ nets that hold up to 18 shells. Shells are then transported to the pearl farm where, following inspection and sorting, the mussels are suspended vertically from rafts made from sealed polythene pipes that are so arranged as to leave sufficient space between both mussels and nets to allow the bivalves to recuperate (for at least a month) to feed, to grow, and indeed to spawn. ‘Mother shells’ are kept separated from ‘sacrifice’ mussels.
- Nucleation occurs at the farm using American-trained technologists and American implant technology based in traditional Japanese methods. Once cleaned, the ‘mother shells’ are held in troughs located in the implant lab.
- Because of their large size American freshwater mussels are multi-nucleated using MOP beads of various shapes.
- Three types of pearls are produced: hemispherical blister pearls, bead nucleated whole pearls of various shapes, keshis.
- Following recuperation under the controlled conditions of laboratory-based ‘ponds’, the implanted mussels are returned to the pearl farm for periods ranging from 1½ (for blister pears) to 3-5 years (for whole pearls) depending on the nature of the implant.
- For blister pearls the shells are first cleaned, their cultured blister pearls sawn from the shell, and the sawn edges shaped and polished either to free from or calibrated sizes.
- Fancy shape free pearls, cultivated in the body of the mussel, are covered by killing the mussel at harvest. Due to shaped nuclei these pearls are available in a range of interesting shapes that include marquise, teardrop, bar, marquise, disc, triangle etc.,--with and without bumps, circles, and nodelles (fish-tails).
- Factors determining the grade of these pearls include their luster, orient, color, shape and color.
- Over the years mortality rates for American freshwater cultured pearls have been reduced to less than 5%.

Nineteenth Century Jewellery

By Peter Hinks
Faber and Faber Ltd
1975 ISBN 0-571-10650-1

Faber and Faber writes:

More jewellery was made in Europe during the nineteenth century than in any other period before or since. What is more, the jewellery was extremely varied—the predilections, obsessions and changing circumstances of England, France, Italy and Germany, for example, being faithfully reflected in their pieces—and much was of the highest quality. The discovery of diamonds in South Africa, the gold rush in the States and Australia, the theatre, war, archaeology, the latest ‘Novelty’, all were sources of inspiration for the jeweler. Nineteenth Century Jewellery both describes in absorbing detail the beautiful and sometimes bizarre ornaments of an extraordinary era and tells us much of the craftsmen who made them and the people through whose hands they passed: women of taste and fashion, shopmen, peddlers, confidence tricksters. It is probably the first book on the subject to cove the whole of Europe comprehensively.

The Revolutionary, Napoleonic, post Napoleonic, mid-century, Second Empire, High Victorian and Fin de Siecle styles of jewellery are all pinpointed and analyzed. And there are also useful chapters on the Arts and Crafts Movement, on Art Nouveau, peasant and mourning jewellery and on collecting, and an appendix of the gold and silver marks of ten countries. The development of the great centers of manufacture both in Europe and America is clearly traced. The selection of pieces illustrated is unusual and arresting.

Peter Hinks is Sotheby’s leading expert on nineteenth century jewellery.