Descendant Of The Pharaohs

Sylvia Hochfield writes about Egypt’s antiquities council's campaign to repatriate artistic icons from museums around the world + Zahi Hawass, the passionate secretary general of Egypt’s Supreme Council of Antiquities @ http://artnews.com/issues/article.asp?art_id=2039

Dubai Topped $10 Billion In Diamond Transit Trade In 2005

Chaim Even-Zohar profiles Dubai, the tougher policies of Dubai Multi Commodities Center (DMCC), the Dubai Diamond Exchange (DDE), the Kimberley Authorities + the business angle @ http://www.idexonline.com/portal_FullEditorial.asp?TextSearch=&KeyMatch=0&id=25483

Synthetic Or Artificial

2007: Even today many don't know/understand the difference (s) between synthetic and artificial gemstones. The minute you mention synthetic they will ask if it's glass or plastic; to my surprise even gemologists, jewelers and traders ask the same. I call it momentary autism. They go blank/inert. I think gemological education should be perceived as a life long learning endeavor.

(via The Journal of Gemmology, Vol.VII, No.6, April, 1960) A E Farn writes:

Most gem enthusiasts have at some time or other either attended a gemological exhibition, or proudly shown their own collection of gems to friends and relations—always to be asked the inevitable question, ‘how much are they worth?’ To the keen collector, this is an irritating question, since it indicates clearly where the interest lies and how the average person reacts to such terms as gemstones or jewelry. Seldom does one meet the true appreciation of beauty or rarity, but always the eternal ‘how much?’

Unfortunately certain elements in our society readily apply their criminal psychology to this materialistic interest in valuables so quickly evinced by the more greedy or gullible section of the public. Thus, when a new material came on to the market and displayed tremendous fire and attraction for a price low in comparison to diamond it afforded possibilities which the unscrupulous were not slow to realize. The new material’s trade name of fabulite seemed coined specially for word play—fabulous for the credulous! It was not until some fairly recent occasion that I was asked by a gem dealer, who wanted to satisfy a customer’s enquiry, whether it was intended to simulate diamond and if it was a synthetic stone.

Answering rather quickly without very serious thought, I replied that it certainly was not intended to simulate diamond but doubtless it could be so used. It was not synthetic diamond, since its formula was SrTiO3, strontium titanate, but it could be described as a synthetic stone. Since then I have had second thoughts. I began to wonder if it was correct to describe this product as synthetic, and without going into the various aspects and methods of manufacture of synthetics generally I wondered whether it was correct so to describe strontium titanate.

Being weak on etymology I could only have recourse to what I had been taught, and as far as I could remember a synthetic stone is a stone which has the same chemical composition, refractive indices and specific gravity as its natural counterpart.

If a synthetic ruby be analyzed it would correspond with natural ruby and similarly in the case of sapphire. With synthetic spinel this is not quite the same, as here there is an excess of alumina in the composition and the properties are slightly higher in R.I and S.G than those of natural spinel. It would seem to be hair-splitting, but even synthetic spinel is not a true synthesis of natural spinel. It did not intend to propound this particular case, but it slipped in as a natural sequence.

What I really wanted to focus on is: strontium titanate, is it a synthetic, since so far as is known there is no naturally occurring mineral? Certainly it is an artifact as indeed are all synthetics, whether corundum, spinel, rutile or emerald. The Concise Oxford dictionary gives synthesis as ‘combination, composition, putting together. Chemically: artificial production of compounds from their constituents.’ Jarrold’s dictionary of difficult words gives synthesis as ‘combination of parts into a uniform whole. Synthetic—pertaining to synthesis and adjectivally as artificial.’ Webster’s Compendium carefully states, ‘synthetic gems having similar chemical composition to natural corundum and spinel and which in physical and optical properties approximate to these gems are made in an oxy-coal gas furnace (Verneuil process)’. Anderson’s Gem Testing gives: ‘synthetic stones, manufactured stones which have essentially the same composition, crystal structure and properties as the natural mineral they represent.’

It would seem, therefore, that a consensus of opinion is against terming an artifact of no known natural counterpart as a synthetic from a gemological view. Incidentally, most so called synthetics which have a counterpart in nature are all certainly harder than fabulite, which has a softness too low to admit of normal jewelry usage. It would seem therefore that strontium titanate is in fact an artificial stone and should be so described.

Sphalerite

(Blende or Zinc Blende)
Chemistry: Zinc sulphide
Crystal system: Cubic; generally in tetrahedral but also cube, octahedral, dodecahedral and trisoctahedral; twins common; massive.
Color: Transparent to translucent; yellow, green, colorless; non-gem nearly black in color.
Hardness: 3.5 - 4
Cleavage: Perfect: dodecahedral (6 directions); fracture: brittle, uneven.
Specific gravity: 4.09
Refractive index: 2.37; SR
Luster: Resinous to adamantine
Dispersion: Very high
Dichroism: -
Occurrence: Chief ore of zinc; Central Africa; Mexico; Spain.

Notes
Collector’s stone; difficult to cut due to cleavage; soft; scratches easily; has been used as prism in high R.I refractometers; may look like zircon; spectrum: 3 bands in red-690,667,651nm; faceted.

How To Separate Natural Pink Diamonds From Their Treated Counterparts

- Body color
- Color evenness
- Strain patterns
- Ultraviolet luminescence
- Spectrum

Ultraviolet luminescence + spectrum analysis are the two important tests.

Judgment Of Paris: California vs. France And The Historic 1976 Paris Tasting That Revolutionized Wine

Good Books: George M. Taber writes about the inside tale of the dramatic tasting session that transformed the wine industry. It's a trip down the memory lane. You can feel the contagious passion for his subject + he has an eye for telling detail. The book is a must-read.

This reminds me of diamond grading. Someone should do the same to transform the diamond grading tale. There is a petty war going between different diamond grading laboratories and institutes who are perceived as the gold standards of the industry. I believe it will be an interested trip down the memory lane.

Book Description:
Told for the first time by the only reporter present, this is the true story of the legendary Paris Tasting of 1976 -- a blind tasting where French judges shocked the industry by choosing unknown California wines over France's best -- and its revolutionary impact on the world of wine.

The Smithsonian's National Museum of American History houses, amid its illustrious artifacts, two bottles of wine: a 1973 Stag's Leap Wine Cellars Cabernet Sauvignon and a 1973 Chateau Montelena Chardonnay. These are the wines that won at the now-famous Paris Tasting in 1976, where a panel of top French wine experts compared some of France's most famous wines with a new generation of California wines. Little did they know the wine industry would be completely transformed as a result, sparking a golden age for viticulture that extends beyond France's hallowed borders -- to Australia, Chile, South Africa, New Zealand, and across the globe.

Then Paris correspondent for Time magazine, George M. Taber recounts this seminal contest and its far-reaching effects, focusing on the three gifted unknowns behind the winning wines: a college lecturer, a real estate lawyer, and a Yugoslavian immigrant. At a time when California was best known for cheap jug wine, these pioneers used radical new techniques alongside time-honored winemaking traditions to craft premium American wines that could stand up to France's finest.

With unique access to the main players and a contagious passion for his subject, Taber renders this historic event and its tremendous aftershocks in captivating prose, bringing to life an eclectic cast and magnificent settings. For lovers of wine and anyone who enjoys a story of the entrepreneurial spirit of the new world conquering the old, this is an illuminating and deeply satisfying tale.

Here is what Publisher's Weekly has to say about the book:
In 1976, a Paris wine shop arranged a tasting as a gimmick to introduce some California wines; the judges, of course, were all French and militantly chauvinistic. Only one journalist bothered to attend, a Time correspondent, looking for a possible American angle. The story he got turned out to be a sensation. In both red and white blind tastings, an American wine won handily: a 1973 Stag's Leap cabernet and a 1973 Chateau Montelena chardonnay. When the story was published the following week, it stunned both the complacent French and fledgling American wine industries—and things have never been the same since. Taber, the Time man, has fashioned an entertaining, informative book around this event. Following a brisk history of the French-dominated European wine trade with a more detailed look at the less familiar American effort, he focuses on the two winning wineries, both of which provide him with lively tales of colorful amateurs and immigrants making good, partly through willingness to experiment with new techniques. While the outrage of some of the judges is funny, this is a serious business book, too, sure to be required reading for American vintners and oenophiles.

Christian Vannequé, former chief sommelier at the Tour d'Argent restaurant in Paris and one of the judges at the Paris Tasting writes:
"Nearly thirty years later, Taber's book outlines an historic event that is relevant, captivating and compelling -- even for non-wine aficionados. The petty wine war that the Paris Tasting set off had one big winner: good wine. And one big loser: good wine...from France."

Industrial Strength

Peter Schjeldahl writes about Richard Serra’s work as art + its otherness @ http://www.newyorker.com/arts/critics/artworld/2007/06/11/070611craw_artworld_schjeldahl

Plonk Testing

2007: I like the the term plonk testing. Today the concept may be tricky because of the proliferation of sophisticated colored stones, treated, synthetic and assembled stones of all qualities. For the practising gemologists, gem dealers + jewelers the basic tenets are still the same: visual observation + the right approach. This requires knowledge, interpretation skills, Zen-like patience, discipline, analytical skills + hawk's eye to spot the unknown gemstone (s).

(via The Journal of Gemmology, Vol.VII, No.5, January, 1960) A F Farn writes:

My fellow gemologist and friend, Dr E H Rutland, delights in, and is an expert at ‘Plonk Testing’. To ‘plonk’ (an unusual gemological term meaning ‘to go off the deep end’) is to view a gemstone, usually not one of the better known gemstones, which has recently come to hand and to state categorically what the stone is—usually to the delight of the possessor since he is usually armed with details in advance.

A rule of thumb approach and a keen eye backed by knowledge of gemology are the essentials to expertise. Possibly the hardest school is that which backs its judgment by placing not the stone upon the refractometer but its hand in its pocket.

Having attended many lectures and listened to much theory on the subject of gem testing and the rival and relative merits of certain instruments, I am reminded of certain examination questions phrased in the following style:

- What do you consider the equipment necessary to furnish a model laboratory? or
- What are the most important or imperative instruments a gemologist’s needs?

To answer such questions one usually has or shows a marked preference for certain instruments or gives obvious indications of techniques favored by an instructor. Some people are keen on refractometer work, others specific gravity or the spectroscope, and some of course combine the use of each. There are some tests so rudimentary and positive that is needless to go further, which of course admits knowledge of gemology.

Whilst testing by sight is not necessarily accurate, it is usually applied with a background of knowledge and reasoning. I should have stated earlier that perhaps a lens is permitted, but no more. An instance of such testing could be a completely colorless (or white) stone, whichever term is preferred, with one or two minute bubbles, no double refraction discernible but perhaps a slight ‘chatter-marking’—a sure sign of heating of corundum. Therefore the stone would a synthetic corundum. This, of course, is a very obvious instance. There are, doubtless, countless others which will spring to mind. Most gemologists, of course, test stones for enjoyment at leisure; professionals test against the clock and seldom have much time to browse amongst the undoubted beauties of inclusions in Burma or Siam rubies. The latter, though less expensive commercially, are amongst the most beautiful stones from an inclusion point of view. Having tested some tens of thousands of stones I am afraid I do not linger too long in throes of delight on seeing either a Ceylon zircon spectrum or hessonite garnet inclusions. These are merely speedy recognition signs for testing.

Quite recently a parcel of 284 cts of mixed round stones of various colors, and approximately 3500 stones came into my possession. My first reaction was to glance swiftly through the stones spread out on the table on a sheet of white paper and pick out any likely stones, i.e those which looked interesting. Most seemed to me to be the product of Ceylon—later proved correct. Two stones only proved to be of a likely hue and appearance. The remainder I sorted by color into piles of brown hessonite garnets, red/pink Ceylon garnets, pale blue, green and yellow Ceylon sapphires, and an intriguing assorted colored section of zircons of every hue. The colorless portion, thank goodness, was very small—these are always a headache except in this instance.

Having decided the piles on color, the next step was to check by spectroscope. Every pink/red garnet was swiftly pushed into a spot of light from an intensity lamp focused onto the table, and the garnets fed from left to right. With the spectroscope held in the right hand some 600 stones were accurately observed and dealt with in about two hours (having all the same spectrum helped a lot). The zircons came next and the same procedure took place, except that here some had a full Ceylon spectrum and some just a hint of the 6535 Å line, some metamicts. Again this was a speedy test of approximately similar quantities and time. A point of interest here is that the quick focus spot method of scattered light will give a sharp absorption spectrum from a stone of less than one-tenth of a carat whereas by transmitted light through a microscope it would be flooded out and eye would quickly become fatigued. The next parcel, possibly the largest in number, were those ‘plonked’ as hessonites. Here there could be (I hoped) a spessartite or two and the spectroscope came into play once again. None of the stones showed a spectrum, my eye being focused on the blue section end looking for a sign of manganese in the make-up of the stone. There was no need to take the R.I of any of these stones since a quick check of samples by lens and use of corn tongs showed all had the familiar diopside crystal inclusions—the characteristic sign of hessonite. After a time, when one has concentrated solely on one color of gemstone, the eye becomes attuned and exceedingly quick to distinguish any unusual stone. These three groups had reduced the bulk by about 85%.

The next lots were the potential Ceylon sapphires. Knowledge of color shades indicated no synthetics being present, since these latter stones are usually a finer color than their natural counterparts.

Although the spectroscope was speedy in picking out green-blue sapphires, it only gave a hint of chromium being present in the pale shades of blue sapphires. This was interesting to note, since the evidence was also proved by the slight change from pale blue to pale lavender or pink when being transferred from daylight on the table to the artificial light on the focus from the intensity lamp. Although these stones were small, quite a fine bright fluorescent line could be picked up by eye on tilting the spectroscope to the left. This is a useful tip when ‘searching’ for a spectrum, e.g commercial quality Ceylon sapphires do not readily or easily show a 4500 Å line, but tilting the spectroscope will often bring it into view. (In the latter case the spectroscope is tilted to the right). Having hinted perhaps that my intuition was carried out in an atmosphere partial to absorption spectroscopy, I must state the obvious and point out that for a gemologist it is red on the left, blue on the right, when looking through a spectroscope. The pale blue and yellow sapphires together were checked by lens and tongs for chatter-marking and feathers, of which fortunately there was an abundance. Ceylon liquid feathers and two-phase inclusions are a joy in speedy establishment of origin.

The hard core of ‘seeded’ stones now came to be tested. Several mauve/brown stones proved to have the refractive index of natural spinel, two other deep golden brown stones were chrysoberyl, whilst the remainder of colorless stones, were quartz and topaz respectively. Considering its travels and origins I was lucky not to find a single paste or synthetic stone in the parcel.