They have been cut in half and the sawed surfaces polished. Both localities produce fine examples of prismatic amethyst crystals.
de Profesor Rafael Ramírez), Veracruz and Amatitlán, Mun. Most amethyst localities produce crystals that are not long and slender like these. Mexico is well known to collectors for two amethyst localities that produce beautiful prismatic crystals of amethyst. The links below will show you what good specimens of quartz from various localities in the United States look like and as you scroll through them you will see that some of them produce fair to quite good specimens of amethyst. To see pictures of amethyst from various localities in the United States, click on the following links and scroll through the various quartz localities. In South Carolina near the town of Due West, some spectacular specimens of amethyst have been produced. To a mother, even ugly children are beautiful. Thunder Bay, Ontario, Canada is well known and in some circles even cherished for the modest specimens of small drusy amethyst crystals found there. There are many localities for amethyst in North America. There are certainly well over a thousand localities in the world that have produced amethyst specimens of varying quality. Hassan’s excellent article in the 1974 Canadian Mineralogist, Vol.59, pp 719-728. Want to know more? No? Well, on the off chance that you do, refer to A. Well, that’s the general idea at any rate. The intensity and color of amethyst depends on how much iron is in the quartz crystal, where it is located in the atomic structure of the quartz, and the possible presence of aluminum which may impart a smoky color to the amethyst. That means that the color center absorbs all the colors except those in the purple/violet region which are then transmitted and reflected to our eyes. Natural ionizing radiation in the ground then strips an electron from the ferric iron atom this activates the color center giving amethyst its color.
When the ferric iron is incorporated into the structure of the quartz crystal it forms “color centers”. This is incorporated into the structure of the growing crystal. When the variety of quartz called amethyst is being formed, the water supplying the nutrients for the growing crystal carry some dissolved iron in its ferric (Fe+3) state. Each stone and thus represented one of the 12 tribes of Israel. The bible mentions amethyst as one of the twelve stones in the breastplate of the High Priest. Amethyst is a variety of quartz and has basically the same chemical composition, atomic structure, and physical properties of quartz: (hardness 7, specific gravity of 2.65 g/cc etc.) Books on geology and mineralogy usually list it under quartz. They thought quartz was water that had been frozen so hard that it would never melt. The ancients thought amethyst was different from quartz. I think this tale of ancient amethyst cups may be mostly a myth. I don't know of a single amethyst cup that has been preserved from antiquity. Although as far as I know none of the ancient sources of amethyst ever produced single crystals of amethyst sufficiently large from which cups could be made if a few large crystals of amethyst were found, they must have been very rare creatures indeed. Roman emperors are said to have had cups/goblets made from amethyst in the belief that the cup would counteract any poison and keep them from getting drunk. The name amethyst comes from the Greek “α-μεθηστos” which means “not drunk”. © Rock Currier June 1997 Amethyst, its name, some history, and why it has its beautiful color. Amethyst Specimens Everything you always wanted to know, and needed to know about amethyst specimens, but were afraid to ask.
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