Canada

Fort Hope pegmatite group

Kenora district
Ontario
Canada


Rossmanite was found in three highly evolved pegmatite dykes: Rubellite dyke south and north and the JJ dyke. Most of the crystals are elbaite, but some just cross over into the rossmanite field.

sample
Fort Hope rubellite. Photo credit: Frederick Breaks

comp


 

Composition

A typical rossmanite composition is
X([]0.51Na0.49Ca0.00) Y(Li1.19Al1.81) ZAl6.00 (BO3.00)3.00  (Si5.89Al0.11)O18.00   [(OH)3.71F0.29]


References:

Breaks, F.W., Tindle, A.G., and Selway, J.B. (2008) Electron microprobe and bulk rock and mineral compositions from rare-element pegmatites and peraluminous, S-type granitic rocks from the Fort Hope pegmatite field, north-central Superior Province of Ontario. Ontario Geological Survey, Miscellaneous Release Data, 235.

last upgraded: 9-Dec-2015