Mineral description : Talc

Talc from Laisaliden.
With dolomite.
Talc from Bastnäs.
I think the green needles are aktinolite.
A piece of massive talc from Sala silver mine.
Talc from Ihalainen, Finland.
As blue veins in limestone.

Mineral class Silicates : Phyllosilicates : Serpentine - Talc - Pyrophyllite group.
Chemical formula Mg3(OH)2(Si4O10)
Crystal system Monoclinic.
Habitus Rarely as crystals, sometimes as hexagonal lamellaes. Often as folded foliated or homogenous masses.
Cleavage Perfect, fracture uneven.
Hardness 1
Density 2.58-2.83
Color Pale to dark green, gray, brownish or white. Even pink and blue exists. Translucent.
Streak White.
Luster Pearly to dull or greasy.
Description One of the industrial mierals. Used for a number of purposes, metal casting ....
Occurance A major ingredience of soapstone. Often created by metasomatic transformation of other minerals. Found in dolomitic rocks, ultrabasic rocks, in scarn of many mines and in schist.
Associates Magnesite, Dolomite
Notes Greasy feeling. Bendable lamellaes but not flexible.
Locations A common mineral in Sweden.
  • Falu mine.
  • Svartviksgruvan, Svärdsjö, Kopparbergs län. (over 20 000 tons mined)
  • Garpenbergsgruvan, Kopparbergs län.
  • Major part of the soapstone (täljsten) occurance along the caledonides. As Handöl and Lermon, Jämtland.
  • Laisholm, Hemavan, Västerbotten. As light green veins in soapstone witm dolomite crystals.
  • Ihalainen limestone quarry,Lappeenranta, Finland. As blue and pink veins in calcite.

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Last changed : 1998-03-07