Anorthite (Var: Bytownite)

Bytownite is a calcium rich member of the plagioclase solid solution series of feldspar minerals. It is usually defined as having "%An" between 70 and 90. Like others of the series, bytownite forms grey to white triclinic crystals commonly exhibiting the typical plagioclase twinning and associated fine striations. Bytownite occurs in gabbro intrusions and in metamorphic complexes. The mineral was first described in 1835 and named for an occurrence at Bytown (now Ottawa), Canada. This is a fine example of the species.

Size: 42mm x 20mm x 27mm

Collection: Ex- Martin Zinn Collection

This photo has been shown 252 times