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Berthierine crystals - click for larger pic
Berthierine crystal
Photo by Modris Baum
© Modris Baum

Berthierine crystals - click for larger pic
Berthierine crystals
Modris Baum photo
© Modris Baum

Berthierine crystals - click for larger pic
Berthierine crystals
Photo by Doug Merson
© Doug Merson

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Home > Mineral Descriptions > Berthierine



Berthierine
Fe22+Al(Si,Al)O5(OH)4

     Berthierine, a member of the kaolinite-serpentine group, is found as pseudomorphs at MSH. It is a pseudomorph after a mineral with a layered structure, possibly some mineral of the mica group.

PHYSICAL CHARACTERISTICS:

Color is usually greenish yellow, yellow or brown.
Luster is dull.
Diaphaneity is translucent.
Crystal System is monoclinic; Cm.
Crystal Habits include sharp pseudo-hexagonal prismatic
   pseudomorphs to 5mm terminated with pinacoid.
Cleavage {001} is perfect.
Fracture is uneven.
Hardness is 2 - 2.5.
Specific Gravity is approximately 3.5 g/cm3.
Streak is white.
Associated Minerals include aegirine, allanite, apophyllite series,
   calcite, microcline, natrolite, rhodochrosite and titanite.
Distinguishing Features: Crystal habit and color.
Origin: Named in 1832 after Pierre Berthier (1782-1861),
   French chemist.

CLASSIFICATION:

Dana System
# 71.1.2c.2

Strunz Classification
# VIII/H.27-70

REFERENCES:
MinRec 21:299 (1990), Dana 8:1423-1424 (1997)

DISTRIBUTION AND RARITY AT MONT SAINT-HILAIRE:

MSH
¤¤¤

PE
--

AP
¤¤

MX
--

SS
--

MC
--

HF
--

BR
--

SX
--

FR
--

Legend

Berthierine crystals - click for larger pic
Berthierine crystal
Stephan Wolfsried photo
© Stephan Wolfsried

Berthierine crystals - click for larger pic
Berthierine crystals
Stephan Wolfsried photo
© Stephan Wolfsried