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Brookite crystal
Photo by Doug Merson
© Doug Merson
Brookite crystals
Steven Stuart
© Steven Stuart
TiO
Brookite is moderately widespread species at MSH.
PHYSICAL CHARACTERISTICS:
Color is usually dark blue, black, very dark brown to red-brown.
Luster is adamantine to submetallic.
Diaphaneity is opaque to translucent.
Crystal System is orthorhombic; Pbca
Crystal Habits include sharp well-formed, complex short prisms;
equant pseudohexagonal dipyramids and rarely of tabular habit.
Cleavage {120} is indistinct and {001} is more indistinct.
Fracture is subconchoidal to uneven.
Hardness is 5.5 – 6.
Specific Gravity is approximately 4.1 g/cm
Streak is white to grey.
Associated Minerals include aegirine, albite, analcime, biotite,
calcite, dolomite, elpidite, natrolite, quartz and siderite.
Distinguishing Features: Crystal habit.
Origin: Named in 1825 after Henry James Brooke (1771-1857),
English mineralogist.
CLASSIFICATION:
Dana System
# 4.4.5.1
Strunz Classification
# IV/D.15-10
REFERENCES:
MinRec 21:300 (1990), Dana 8:246-247 (1997)
DISTRIBUTION AND RARITY AT MONT SAINT-HILAIRE:
MSH
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