Kernite

Hydrated sodium borate hydroxide mineral

Kernite, also known as rasorite, is a hydrated sodium borate hydroxide mineral with formula Na2B4O6(OH)2·3H2O. It is a colorless to white mineral crystallizing in the monoclinic crystal system typically occurring as prismatic to acicular crystals or granular masses. It is relatively soft with Mohs hardness of 2.5 to 3 and light with a specific gravity of 1.91. It exhibits perfect cleavage and a brittle fracture.

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