Shimazakiite ore exhibited at Mining Museum of Akita University — Photo: 掬茶 · CC BY-SA 4.0
Shimazakiite
Shimazakiite is an IMA-recognized mineral species in the borate class, with the chemical formula Ca₂B₂O₅.
It crystallizes in the orthorhombic crystal system (space group P2_1/c).
Key properties: Mohs hardness 4.5; specific gravity 2.81; White streak; Vitreous luster; optically biaxial.
IMA symbol Smz, IMA status: approved, named in 2010.
Found in an irregular vein in crystalline limestone near gehlenite-spurrite-bearing contact metamorphic rocks (skarn).
It is found associated with Takedaite, sibirskite, olshanskyite, parasibirskite, nifontovite, calcite, an uncharacterized hydrous calcium borate.
The mineral was named to honor Emeritus Professor Hidehiko Shimazaki (b. 1939), University of Tokyo, Japan, in recognition of his outstanding contributions to skarn mineralogy.