Category Borate minerals Strunz classification 6.AB.10 | Formula
(repeating unit) Be2(BO3)(OH,F)•H2O Dana classification 26.1.1.1 | |
Crystal system 1T polytype: Trigonal
2H polytype: Hexagonal
2T polytype: Trigonal Crystal class 1T polytype: Pyramidal (3)
2H polytype: Pyramidal (6)
2T polytype: Ditrigonal pyramidal (3m) | ||
Berborite is a beryllium borate mineral with the chemical formula Be2(BO3)(OH,F)·(H2O). It is colorless and leaves a white streak. Its crystals are hexagonal to pyramidal. It is transparent and has vitreous luster. It is not radioactive. Berborite is rated 3 on the Mohs Scale.
Berborite occurs in 1T, 2T, 2H polytypes.
It was first described in 1967 for an occurrence in the Lupikko Mine, Ladoga Region Karelia Republic, Russia. It has also been reported from Tvedalen, Larvik, Vestfold, and Siktesøya Island, Langesundsfjord, Porsgrunn, Telemark, Norway. It occurs in serpentine altered dolostone in association with skarn enriched in tungsten, strontium, beryllium and boron in the Keralia occurrence and in vugs with natrolite and thomsonite in Norway.