Definition of Actinolite

(n.)
A bright green variety of amphibole occurring usually in fibrous or columnar masses.
  

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actinolite
\ac*tin"o*lite\ (&?;), n. [gr. &?;, &?;, ray + -lite.] (min.) a bright green variety of amphibole occurring usually in fibrous or columnar masses.

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Noun
1. a green mineral of the amphibole group; calcium magnesium iron silicate
(hypernym) amphibole
(member-holonym) amphibole group

General Information:
 Chemical Formula:
Ca2(Mg,Fe++)5Si8O22(OH)2
 Composition:
(Molecular Weight = 875.45 gm)
Calcium 9.16 % Ca
Magnesium 8.33 % Mg
Iron 12.76 % Fe
Silicon 25.66 % Si
Hydrogen 0.23 % H 
Oxygen 43.86 % O 
 Empirical Formula:
Ca2Mg3Si8O22(OH)2Fe2+2
 Environment:
Metamorphic rocks.
 IMA Status:
Approved IMA 1978
 Locality:
Common world wide.
 Name Origin:
From the Greek, aktinos, meaning "ray" in allusion to actinolite's fibrous nature.
Physical Properties:
 Cleavage:
[110] Perfect, [110] Perfect
 Color:
green, green black, gray green, or black.
 Density:
2.98 - 3.1, Average = 3.04
 Diaphaniety:
Translucent to transparent
 Habits:
Bladed - Aggregates of thin lath-like crystals (e.g. kyanite)., Radial - Crystals radiate from a center without producing stellar forms (e.g. stibnite), Fibrous - Crystals made up of fibers.
 Hardness:
5.5 - Knife Blade
 Luminescence:
Non-fluorescent.
 Luster:
Vitreous (Glassy)
 Streak:
white
More details...

Ca2(Mg,Fe)5Si8O22(OH)2

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