© R.W. Wise Portrait of a disappointment! Young girl panning for rubies and sapphires in a stream in Chantaburi Province, central Thailand.

A combination of rarity, beauty, supply, and demand! Red stones are rarer, and demand exceeds supply; therefore reds will cost more. Obviously, the market enforces universal standards.

For example, one excellent quality grading system, ColorScan, developed by the American Gemological Laboratories, identifies sixty different color combinations of hue/tone in blue sapphire. Each of these is associated with a specific market price. The Guide, an important industry pricing publication, identifies eleven different quality-pricing grids for blue sapphire, and cautions that even these do not cover the entire range of available qualities.16

A very stringent standard exists for the grading of colorless diamond. This standard, developed in the 1950s by the Gemological Institute of America has, with modification, become accepted worldwide.17

Precious versus semi-precious: a distinction without a difference
The question “Is it a precious or semi-precious stone?” is an expression of pure market snobbery. As has been already shown, the term “preciousness” has had different meanings at different periods in different cultures. In earliest times, it had no meaning at all. The term semi-precious is today as meaningless as the term semi-pregnant or semi-deceased. That this term is still in general usage points only to the fact that many of the gemstones described here still lack a degree of market acceptance, and still may be purchased at relatively low prices.

Several gem species and varieties discussed in Part II of this book are fairly recent discoveries: tsavorite garnet, tanzanite, and malaya garnet were completely unknown just fifty years ago. In many cases these new precious gemstones are rarer and more beautiful than those gems that have traditionally been called precious.
To the astute aficionado “semi-precious” should translate as “buying opportunity.” The true lover of gemstones looks at the object without regard for the verbal baggage it may carry along with it. If the foregoing discussion has demonstrated anything, it is that the whole idea of preciousness is fluid. In the world of gemstones, if it is rare and beautiful, and if demand is strong, it is precious.