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Nordstrandite aggregates
Photo by Violet Anderson
© Royal Ontario Museum
Nordstrandite crystals
© Doug Merson
Tabular nordstrandite
2mm
Photo by John Veevaert
© Trinity Mineral Company
Al(OH)
Nordstrandite is relatively rare at Mont Saint-Hilaire. It is one of three polymorphs Al(OH) at MSH, the others being doyleite and gibbsite.
PHYSICAL CHARACTERISTICS:
Color is usually colorless, white, pink, beige and pale green.
Luster is vitreous to pearly.
Diaphaneity is transparent to translucent.
Crystal System is triclinic; 1.
Crystal Habits include aggregates of blocky, tabular crystals to
2mm and botyroidal aggregates.
Cleavage {110} is perfect.
Fracture is uneven.
Hardness is 3.
Specific Gravity is approximately 2.4 g/cm
Streak is white.
Associated Minerals include aegirine, albite, analcime, ancylite,
calcite, dawsonite, dolomite, doyleite, fluorapatite, fluorite, gonnardite,
lizardite, microcline, pyrite, rutile, sodalite, siderite, zircon and
UK #53 (to be described soon).
Distinguishing Features: Crystal habit.
Origin: Named in 1958 after Robert A. van Nordstrand (b. 1917),
Sinclair Research Laboratories, U.S.A..
CLASSIFICATION:
Dana System
# 6.3.3.1
Strunz Classification
# IV/F.02-30
REFERENCES:
MinRec 21:327 (1990), Dana 8:281-282 (1997)
DISTRIBUTION AND RARITY AT MONT SAINT-HILAIRE:
MSH
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Nordstrandite crystals
© Stephan Wolfsried
Nordstrandite crystals
© Stephan Wolfsried