1) Calcium mineral 
Studenitsite is a rare borate mineral with chemical formula of NaCa2[B9O14(OH)4]·2H2O. Studenitsite has a vitreous luster, a Mohs hardness of 6 and color of light-dirty yellow. It is a monoclinic mineral and belongs to the space group P2/c. The basic unit of the crystal structure[B9O14(OH)4]5-layers has a Miller Index of (001). Studenitsite has a...