England
Cornwall
St. Austell
Dorothy china clay pit
Li-mica granite
Rossmanite plus elbaite from Cornwall, England.
The darker shades of green are not rossmanite - the specimen
exhibits considerable zonation into other compositions. Field of view: 4 cm.
Rossmanite occurs in an unusual
sample of tourmaline-quartz veinstone that proved to contain a
number of different tourmaline species. The tourmalines represent the
final crystallization products of a complex
magmatic-hydrothermal crystallization-recrystallization sequence
that saw foitite form early, followed by schorl, "fluor-schorl",
elbaite and rossmanite (Tindle, 2007).
X-site compositions of elbaite and rossmanite tourmalines
from the St. Austell locality span a considerable range
and grade far into the rossmanite compositional field
(AG Tindle, unpublished analyses, 2007b).
References:
Tindle, A.G. (2008) Minerals of Britain and Ireland.
Published by Terra Publishing, Harpenden, Herts AL5 2ZD, England. ISBN-13: 9781903544228
Tindle, A.G. (2007) Personal communication. [a.g.tindle @ open.ac.uk]
last updated 2-Nov-2012