Amethyst Crystal Cathedrals, Brazil Specimen is 10" high and is 7-1/4" wide at the base. Weight: 14.8 pounds. M1299-H - Amethyst Crystal Cathedrals, Brazil. Amethyst is a purple variety of quartz. Silicon dioxide. Hardness 7, (...1/15 as hard as diamond!) Amethyst is the birthstone for February. Amethyst was used as a gemstone by the ancient Egyptians and was largely employed in antiquity for various forms of decoration and in jewelry. Amethyst is considered a semi-precious gemstone. As a general rule the darker the color of amethyst the better the quality of the stone. Dark purple amethyst that is free of impurities and inclusions is highly priced when faceted. For years, cabochons, faceted gemstones, beads, tumbled specimens, and carvings of amethyst has been very popular and prized by the collector and the jewelry folks alike. Present values of amethyst can range from $5.00 to $100.00 per carat. At present some of the most beautiful and prized amethyst is coming our of Uruguay. Amethyst can occur as long prismatic crystals that have a six-sided pyramid at either end or can form as druzes that are crystalline crust that only show the pointed terminations. Amethyst is only one of several quartz varieties. Other varieties that form macroscopic (large enough to see) crystals are as follows: Citrine, Milky Quartz, Rock Crystal, Rose Quartz, and Smoky quartz. The purple color of amethyst is caused by impurities of iron or manganese. Price: $193.00 per piece (You can always remove items from your cart later if you wish)