Orange microcrystals of the very rare mineral yoshimuraite. From one of the only three known localities worldwide: Taguchi Mine, Shidara, Aichi Prefecture, Honshu Island, Japan. — Photo: David Hospital · CC BY-SA 4.0
Yoshimuraite
Yoshimuraite is an IMA-recognized mineral species in the silicate class, with the chemical formula Ba₄Mn²⁺₄Ti₂(Si₂O₇)₂(PO₄)₂O₂(OH)₂.
It crystallizes in the triclinic crystal system (space group P-1). It is a member of the Seidozerite-Bafertisite structural group.
Key properties: Mohs hardness 4.5; specific gravity 4.13–4.2; optically biaxial.
IMA symbol Ysh, IMA status: approved, named in 1961.
Found in the border facies of an alkalic pegmatite cutting a stratiform manganese deposit (Noda-Tamagawa mine, Japan).
It is found associated with Richterite, rhodonite, barian potassic feldspar, \aegirine-augite, " riebeckite, quartz.
In honor of Professor Toyofumi Yoshimura, Kyushu University, Hakozaki, Japan.