Methuen Handbook of Color

By A Korenerup & J H Wanscher
Politikens Forlag, Copenhagen
Methuen London
1961 / 1989 ISBN 0-413-33400-7

Methuen writes:

The third edition of this authoritative pocket color book covers the essentials of color practice and includes an international dictionary of colors with British standard equivalents. A universal ready reference for all those whose jobs or recreation involves color, it now includes names of colors used by British paint manufacturers and colors traditionally associated with the printing ink industry, thus shedding light on the whole field of color in art and science.

The color book is divided into two parts, the Handbook proper and a Color Dictionary. The Handbook explains the basic facts upon which all systems of color identification are based, and describes some important visual effects that apply to color usage generally. The Dictionary consists of plates of 1266 color samples accompanied by descriptive glossaries of color names with an easy cross reference system.

The Color Dictionary is so contrived that a color sample of one’s own can be compared with the charted samples, and an appropriate name selected for it from the color diagrams. On the other hand, the appearance of a named color can be discovered by looking up the color name in alphabetical list and following the reference symbol to the appropriate place on the color plates.

Lists of color names used by British paint manufacturers and those used by the printing ink industry are included, set out in such a way that they can be readily compared with the colors reproduced in the Dictionary.

Corundum Doublets

The most likely place to find doublets and triplets is in antique jewelry. It is also possible to find doublets and triplets in new pieces.

Assembled stones normally consist of two parts (doublets) or three parts (triplets) glued together for the following reasons:

- to provide a better wearing surface.
- to obtain a large stone from two smaller pieces of natural gem material.
- to provide better color and appearance.

The purpose of producing corundum doublet is to have the careless buyer look into the table of the stone, see the natural inclusions on the crown area, then purchase the gem at a high price. This deception is possible because of the thin crown of colorless or light yellowish green sapphire does not influence the color the stone face up (table-up), which is determined by the synthetic material on the pavilion. Few buyers actually check the girdle of the stone. Corundum doublets are easy to detect if the buyer is aware of their features. The careless buyer can easily be fooled.

When you are trying to identify an unknown stone always suspect an assembled stone. To avoid the mother-of-all surprise you should look for the difference in color, luster or inclusions, plane of join, gas bubbles (if any) between the crown and pavilion (base) of the gem material. Doublets consisting of black star sapphire on the crown and pavilion of lower quality natural sapphire is also common. There is also doublet made of a base of a black, non-transparent layer of natural star sapphire topped with synthetic orange sapphire or synthetic spinel (flame fusion). Use good lighting and proper magnification to view the color contrast so that you are able to identify the stone.

Forrest Gump Movie

A memorable quote from the movie:

Forrest Gump (Tom Hanks): My momma always said, "Life was like a box of chocolates. You never know what you're gonna get."

The Federal Trade Commission’s Guide for the Jewelry, Precious Metals and Pewter Industries

FTC writes:

23.14 Misuse of the term "blue white."

It is unfair or deceptive to use the term "blue white" or any representation of similar meaning to describe any diamond that under normal, north daylight or its equivalent shows any color or any trace of any color other than blue or bluish.

More info @ http://www.ftc.gov/bcp/guides/jewel-gd.htm

Emeralds Of Pakistan

By Ali H Kazmi and L W Snee
Geological Survey of Pakistan
Van Nostrand Reinhold Company
1989 ISBN 0-442-30328-9

Van Nostrand Reinhold Company writes:

Emerald has been known to mankind since prehistoric times and yet is one of the rarest of gemstones—found only in a few locations. The uniqueness of emerald is a result of the unusual combination of two chemical elements, beryllium and chromium, that normally are not associated in nature. This special combination is controlled by fascinating geological processes that brought rocks of very different character together under conditions that permitted the formation of these beautiful green gems. Thus, emerald is not only fascinating to the gemologist and mineral collector because of its exceptional beauty but also to the geologist because of the geological process it represents.

Emeralds of Pakistan—geology, gemology, and genesis examines emeralds of Pakistan from three viewpoints—geologic, occurrence, physical and chemical characteristics of the gems, and origin. With scores of figures, including 81 color plates, the book describes and illustrates emeralds of Pakistan and summarizes the geologic occurrence of other worldwide emerald deposits.

Nine chapters and a selected bibliography summarize nearly ten years of research by 12 scientists. Emeralds of Pakistan—geology, gemology, and genesis covers such topics as:

- geology and tectonics of Pakistan
- geologic setting of Pakistan emeralds
- gemological characteristics of Pakistani emeralds
- comprehensive data on inclusions within the emeralds
- chemistry of the emeralds and their host rocks
- microprobe analyses of the emeralds
- geology of world emerald deposits
- origin of emeralds
- selected bibliography

This is the first book of its kind on the geology of emerald deposits of one area in the world. However, the book also presents the best current summary of all world emerald deposits and develops a new classification system for emerald deposits.

Diffusion Treatment Of Natural And Synthetic Sapphire And Ruby

Corundum with sufficient titanium are good samples for the development of asterism (stars) by heat treatment. Asterism can be developed by diffusing titanium into the corundum crystal lattice with appropriate heat treatment apparatus. The technique is very similar to the production of asterism in Verneuil (flame fusion)-grown synthetic sapphires without titanium content. The technique is applied by many companies to produce stones with asterism (stars). In Thailand both natural, synthetic and treated stones are available.

The process consists of :

1. Diffusion treatment of corundum samples in mixture of aluminum oxide and titanium oxide powder. The temperatures required to facilitate the process (diffusing a thin surface layer) may be in the range of 1700 - 1950 degrees centigrade.

2. The samples are then heat treated in a temperature in the range of 1100 - 1500 degrees centigrade permitting the formation of rutile needles in the surface layer.

The asterism (stars) created by this two step process is caused by needles within only a thin surface layer. When properly done, the visual appearance of treated samples may look very similar to that of untreated natural stones.

With careful examination under the microscope + immersion technique (with sample stones: treated + untreated stones) most treated stones can be identified if they are unset (loose stones).

Sting Movie

Memorable quote (s) from the movie:

J.J. Singleton (Ray Walston): I dunno know what to do with this guy, Henry. He's an Irishman who doesn't drink, doesn't smoke, and doesn't chase dames. He's a grand knight in the Knights of Columbus, and he only goes out to play faro. Sometimes plays 15 or 20 hours at a time, just him against the house.

Henry Gondorff (Paul Newman): Roulette? Craps?

J.J. Singleton (Ray Walston): He won't touch them. The croupier at Gilman's says he never plays anything he can't win.

Henry Gondorff (Paul Newman): Sports?

J.J. Singleton (Ray Walston): Likes to be seen with fighters sometimes, but he doesn't go to the fights or bet on them.

Henry Gondorff (Paul Newman): Jesus. Does he do anything where he's not alone?

J.J. Singleton (Ray Walston): Just poker. And he cheats. Pretty good at it, too.

Charles T Munger

One of my favourite quote from Charles Munger.

Charles T Munger, Vice-Chairman of Berkshire Hathaway Corporation writes:

"Never wrestle with a pig, for if you do, you will both get dirty, but the pig will enjoy it."