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Ferrocolumbite crystals
© Doug Merson
(Fe,Mn)(Nb,Ta)
Ferrocolumbite, a member of the columbite family, has been identified during the ’97-’98 Winter. It had been XRD by Malcolm Back at the Royal Ontario Museum, and SEM probed by Robert Gault at the Canadian Museum of Nature.
PHYSICAL CHARACTERISTICS:
Color is usually black.
Luster is sub-metallic.
Diaphaneity is opaque.
Crystal System is orthorhombic; Pbcn
Crystal Habits include prismatic crystals.
Cleavage {010} is distinct.
Fracture is subconchoidal to uneven.
Hardness is 6.
Specific Gravity is approximately 6.0 g/cm
Streak is brownish-black.
Associated Minerals include corundum, donnayite, gmelinite,
gobbinsite, hercynite and phillipsite.
Distinguishing Features: Crystal habits, color and luster.
Origin: Named in 1802 to reflect its composition: the ferrous iron end –
member of the series with ferrotantalite and manganocolumbite.
CLASSIFICATION:
Dana System
# 8.3.2.2
Strunz Classification
# IV/D.18-30
REFERENCES:
Dana 8:354-355 (1997)
DISTRIBUTION AND RARITY AT MONT SAINT-HILAIRE:
MSH
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