hesil
Hesil is a rare and unique mineral that was first discovered in the late 19th century in the Hesil mine in Cornwall, England. It is a complex silicate mineral with the chemical formula Na2Ca2(Si8O20)2(OH)2. The mineral is typically found in granitic pegmatites and is often associated with other rare minerals such as beryl and tourmaline.
Hesil is known for its distinctive crystal structure, which consists of a framework of silicon and oxygen
The mineral has a Mohs hardness of 6.5 and a specific gravity of 2.85. It is typically
Despite its rarity, hesil has been the subject of scientific study due to its unique crystal structure