Szklaryite

Szklaryite
General
CategoryArsenate
Formula[]Al6BAs33+O15
IMA symbolSky
Crystal systemOrthorhombic
Crystal classDipyramidal (mmm)
H-M symbol: (2/m 2/m 2/m)
Space groupPbcm
Unit cella = 47.00 Å, b = 11.83 Å
c = 20.24 Å (approximated)
Identification
Crystal habittiny patch
References

Szklaryite is an extremely rare mineral with the formula []Al6BAs33+O15. It is essentially vacant ("[]"), arsenic-dominant member of dumortierite supergroup, giving a name of szklaryite group. It is one of three quite recently found minerals of this group, the other two being nioboholtite and titanoholtite, all coming from the Szklary village near Ząbkowice Śląskie in Poland. They occur in a unique pegmatite of probable anatectic origin.