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Helvite crystal
C. M. N. sp.
Photo by Violet Anderson
© Royal Ontario Museum
Helvite crystals
© Modris Baum
MnBe(SiO
Helvite, a member of the danalite-helvite-genthelvite series, is far less abundant than genthelvite at MSH. Helvite fluoresces intense deep red under LW and SW.
PHYSICAL CHARACTERISTICS:
Color is varies from bright yellow to lemon-yellow, orange-yellow.
Luster is vitreous, resinous on granular inclusions.
Diaphaneity: transparent to translucent, opaque on granular inclusions.
Crystal System is isometric; 43
Crystal Habits include small tetrahedra to 3mm on edge, with
minor faces truncating the apices of the tetrahedra, free-growing
crystals granular inclusions.
Cleavage {111} is distinct.
Fracture is not apparent.
Hardness is 6.
Specific Gravity is approximately 3.1 g/cm
Streak is white.
Associated Minerals include aegirine, analcime and catapleiite.
Distinguishing Features: Crystal habit and fluorescence.
Origin: Named in 1817 from the Greek helios, sun, alluding
to its yellow color.
CLASSIFICATION:
Dana System
# 76.2.4.1
Strunz Classification
# VIII/J.12-20
REFERENCES:
MinRec 21:314 (1990), Dana 8:1630-1631 (1997)
DISTRIBUTION AND RARITY AT MONT SAINT-HILAIRE:
MSH
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