Pekovite
Pekovite is an IMA-recognized mineral species in the silicate class, with the chemical formula SrB₂Si₂O₈.
It crystallizes in the orthorhombic crystal system (space group Pnma). It is a member of the Danburite structural group.
Key properties: Mohs hardness 6.5–7; specific gravity 3.35; White streak; Vitreous, slightly greasy luster; optically biaxial.
IMA symbol Pko, IMA status: approved, named in 2003.
Within a block of quartz in the moraine of the Dara-i-Pioz glacier, Alai mountain range, Tien Shan, northern Tajikistan. The Dara-i-Pioz massif at the head of the glacier contains B-rich alkaline rocks and pegmatites.
It is found associated with In quartz, intergrown with pectolite, highly strontian fluorite, and aegirine.
The mineral was named to honor Russian mineralogist Igor Viktorovich Pekov (b. 1967), an expert on the mineralogy of alkaline rocks.