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Wöhlerite crystals
Canadian
Museum of Nature sp.
Photo by Violet Anderson
© Royal Ontario Museum
Wöhlerite crystal
© Doug Merson
NaCa(Zr,Nb)Si(O,OH,F)
Wöhlerite is a very rare mineral at Mont Saint-Hilaire. It is one of the earliest minerals to form in the paragenetic sequence.
PHYSICAL CHARACTERISTICS:
Color is usually pale yellow to orange-yellow.
Luster is vitreous to greasy.
Diaphaneity is transparent to translucent and opaque.
Crystal System is monoclinic;
Crystal Habits include thin tabular crystals to 5mm forming
aggregates of crystals.
Cleavage {010} is distinct, {100} and {110} are indistinct.
Fracture is conchoidal to splintery.
Hardness is 5.5 – 6.
Specific Gravity is approximately 3.4 g/cm
Streak is yellowish-white.
Associated Minerals include aegirine, amphibole group, analcime,
ancylite, astrophyllite, biotite, eudialyte, fluorite, marcasite, microcline,
natrolite, paranatrolite, pyrrhotite, titanite and zircon.
Distinguishing Features: Crystal habit and color.
Origin: Named in 1843 after Fredrich Wöhler (1800-1882),
German professor of chemistry.
CLASSIFICATION:
Dana System
# 56.2.4.5
Strunz Classification
# VIII/C.11-10
REFERENCES:
MinRec 21:346-347 (1990), Dana 8:1163-1164 (1997)
DISTRIBUTION AND RARITY AT MONT SAINT-HILAIRE:
MSH
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