Home > Mineral Descriptions > Anorthoclase - (1 Photo)



Anorthoclase
(Na,K)AlSi3O8

     Anorthoclase is another rare mineral species at MSH.

PHYSICAL CHARACTERISTICS:

Color is usually grey (mottled).
Luster is vitreous to pearly on cleavage areas.
Diaphaneity is transparent to translucent.
Crystal System is triclinic; C.
Crystal Habits include phenocrysts.
Cleavage: {001} is perfect and {010} is good.
Fracture is conchoidal to uneven.
Hardness is 6 - 6.5
Specific Gravity is approximately 2.6 g/cm3.
Streak is white.
Associated Minerals include (??).
Distinguishing Features: Crystal habit.
Origin: Named in 1885 from the Greek an, not, plus orthos, right,
   plus klan, to break, alluding to the fact that the cleavages are not
   at a right angle.

CLASSIFICATION:

Dana System
# 76.1.1.6

Strunz Classification
# VIII/J.7-10

REFERENCES:
Dana 8:1607-1608 (1997)

DISTRIBUTION AND RARITY AT MONT SAINT-HILAIRE:

MSH
¤¤¤

PE
--

AP
--

MX
--

SS
--

MC
--

HF
--

BR
--

SX
--

FR
--

Legend