Mineral, Rock, and Gemstone: What's in Their Names?
by Art Smith (continued from page 11)
If you find a gem occurrence that is different from any other, you can create your own
name. However, the name probably would be only as popular and as widely known as your
gemstone material. Naming has resulted in a lot of confusion. One thing you should never do
is use a mineral name, if that mineral is not part of the material. Mineral names imply a
specific composition. The classic erroneous example is smoky topaz. There is no smoky
topaz, and it refers to smoky quartz. When a mineral name is applied to a gemstone and it,
or the gemstone name, has a prefix, then it may not be what the name implies. There are
many misleading examples: Herkimer diamond = quartz, new jade = serpentine, Mexican
jade = calcite onyx, Transvaal jade = garnet, black diamond = hematite, flower turquoise =
antigorite, black onyx = dyed gray quartz, California ruby = garnet, water sapphire = iolite,
that is the mineral cordierite. These are just a few; the list could go on and on. If you do find
your own gem deposit, you should pick a name that is distinctive and cannot be confused
with another gem material or mineral specie. Unlike a mineral, you can even name it after
yourself, if you want. Recently a gem green diopside was found in the Far East. Since the
name diopside has no specific positive gemstone connotation and wanting a more romantic
name, it has been named tashmarine. Again, this name will be only as well-known as the
material is known, but for marketing purposes the name is distinctive enough so it should not
be confused with any mineral or other gem material now on the market. Like tsavorite and
tanzanite that were unheard of 50 years ago, if marketing is successful, it may become a
desirable and valuable gemstone some day.
In recent years some gem names have become more precise. You cannot call a green
beryl an emerald or a green grossular a tsavorite unless they have the green color caused by
chromium or vanadium. Modern analytical methods have allowed a more precise
determination of composition and color in gemstones. This resulted in the composition of
some gemstones to be more standardized. It is interesting to read the Lab Notes in GIA's
Gems & Gemology and see some of the unique minerals and materials that are becoming
known as lapidary objects and as faceted stones. Often what you think you have, you don't
have, but in a few cases the material is more exotic and more rare than what you expected.
REFERENCES: These are the books I use. There are others equally as good.
Clark, A. M. 1993 Hey's Mineral Index: mineral species varieties, and synonyms. St.
Edmundsbury Press, Sulfolk, United Kingdom. This is the best book for finding information
about mineral varieties and discredited minerals. It is somewhat dated and so species status
of the mineral should be double checked with Mandarino (1999) or later lists.
Fourestier, J. de 1999 Glossary of mineral synonyms. The Canadian Mineralogist special
publication 2. This is a good book for a quick check on mineral names. It does not have as
much information on each entry as Clark (1993) but is more up to date.
Gemological Institute of America, Gems and Gemology. A high quality quarterly journal that
anyone interested in lapidary and faceted stones should get and read.
Mandarino, J. A. 1999 Fleischer's glossary of mineral species, 1999. Mineralogical Record,
Tucson, Arizona. All the accepted species to 1999 and their compositions are given. For
new species after 1999, the best place now is the issues of the Canadian Mineralogist.
Webster, R. 1983 Gems, their sources, description, and identification. 4th edition, revised
by B.W. Anderson, Butterworths, London. For in-depth information on gemstones, this
book I find best for faceted stone. There is probably a later edition that covers some of the
gem material that has been discovered after 1983.
Zeitner, J. C. 1996 Gem and Lapidary materials for cutters, collectors, and jewelers.
Geoscience Press, Tucson, AZ. This is the best book for lapidary materials, though some of
the more local materials are not in it.
From the Backbender's Gazette, 2/2003, Houston, TX
Thanks to Art Smith for sharing this article with us, and to Phyllis George, editor, for
sending it to this editor.