Sborgite

Sborgite is a sodium borate mineral with formula Na[B₅O₆(OH)₄]·3H₂O. The formula can be written as the oxide formulation, Na₂O.5B₂O₃.10H₂O. Sometimes called sodium pentaborate pentahydrate it contains the pentaborate anion, (B₅O₆(OH)₄)⁻.

Sborgite is colourless with monoclinic crystals. It was named for Umberto Sborgi, (1883 - 1955), Professor of Chemistry, University of Milan, Italy. Sborgite occurs in Tuscany, Italy and the Furnace Creek district, Death Valley, California, USA. ^[1]

See also

• List of minerals

References

1. ^ http://rruff.geo.arizona.edu/doclib/hom/sborgite.pdf Mineral Handbook

• Curzio Cipriani (1957). "Un nuovo minerale fra i prodotti boriferi di Larderello". Atti Rend. Accad. Lincei 22: 519–525. 
• S. Menchetti and C. Sabelli (1978). "The crystal structure of NaB₅O₆(OH)₄". Acta Crystallographica Section B B34 (1): 45–49. doi:10.1107/S0567740878002289. 
• S. Merlino (1972). "The crystal structure of sborgite, NaB5O6(OH)4.3H2O". Acta Crystallographica Section B B28 (12): 3559–3567. doi:10.1107/S0567740872008349. 
• sborgite
• webmineral.com