gems, corundum, geology.11, Burma.12, Mogok, beryl, emerald, Russia, Malysheva, Ural Mountains, alexandrite, chrysoberyl, pegmatite

It is widely recognized that some gem minerals often occur together in various localities—either in the same host rock or in the same deposit. Gem minerals each require a certain set of physical and chemical conditions for their formation. This edition of the Colored Stones Unearthed column will explore where specific gem minerals are found together and the conditions that produce these distinct geological settings.