Sections
Thumbnails

Actinolite crystals - click for larger pic
Actinolite crystals
© Bill Lechner

Actinolite crystals - click for larger pic
Actinolite crystals
© Modris Baum

Search this site

Powered by FreeFind

Home > Mineral Descriptions > Actinolite - (2 Photos)



Actinolite
Ca2(Fe2+,Mg)5(Si8O22)(OH)2

     Member of the amphibole group, actinolite is rare at Mont Saint-Hilaire.

PHYSICAL CHARACTERISTICS:

Color ranges from dark green to black.
Luster is vitreous.
Diaphaneity is transparent to translucent.
Crystal System is monoclinic;C2/m.
Crystal Habits include acicular crystals to 5mm.
Cleavage: {001} is perfect.
Fracture is uneven to subconchoidal.
Hardness is 5 - 6.
Specific Gravity is approximately 3.2 g/cm3.
Streak is white.
Associated Minerals include anatase, brookite, calcite, elpidite
   and quartz.
Distinguishing Features: Crystal habit.
Origin: Named in 1794 from the Greek aktis, a ray, in allusion
    to its common occurrence as radiating needles.

CLASSIFICATION:

Dana System
# 66.1.3a.2

Strunz Classification
# VIII/F.10-20

REFERENCES:
MinRec 21:294 (1990), DM 8:1346-1350 (1997)

DISTRIBUTION AND RARITY AT MONT SAINT-HILAIRE:

MSH
¤¤¤

PE
--

AP
--

MX
--

SS
--

MC
--

HF
--

BR
¤¤

SX
--

FR
--

Legend