with smaller deposits in Afghanistan

the polished surface catching light evenly across its gentle curves

Black Tourmaline (schorl) is an iron-rich boron silicate

Its vivid yellow-green color is an intrinsic property of the iron in its crystal structure—the color is built into the mineral's chemistry and cannot be altered by any post-formation process

Smoky Quartz Faceted Sterling Silver Earrings Size:0.9"L x 0.4"W x 0.2"T with smaller deposits in AfghanistanFaceted smoky quartz drops that shift from nearly clear to deep tobacco brown depending on the light. Smoky quartz is silicon dioxide colored grey brown to near black by natural irradiation from radioactive elements in the surrounding host rock, which displaces silicon atoms in the lattice and creates color centers that absorb light. The color ranges from pale grey (citrine smoky blends) through warm cognac to deep Cairngorm brown. It forms in