Ruby Kyanite Flame Coaster It has a hardness of

It has a hardness of 7-7

is a common strontium sulfate mineral that forms within certain geodes

and other minerals

Mookaite is a variety of microgranular quartz

as each is unique

Ruby Kyanite Flame Coaster It has a hardness ofRuby Kyanite occurs when red ruby (corundum) crystals form within a blue kyanite matrix. Kyanite is a silicate mineral that forms during regional metamorphism of clay rich sediments, indicating deep burial of a terrain. These pieces are polished into a flame shape. You will receive one piece selected from our current stock. All pieces are of similar size and quality. Average Dimensions: 1. 35 L x 1. 0 W x 3 H inches. Average Weight: 0. 62 pounds