Talc

  • TalcWhat is it and where is it formed?  Talc is a mineral that is found in igneous and metamorphic rocks.  Sometimes it is called soapstone and is a kind of Mica.  It forms when rocks with magnesium in them are changed by erosion or weathering with heat and water. 

  • How and where is it mined?  Talc is mined using open-pit surface mining.  Talc mines are planned well before they are mined so that there will be a constant supply of the kind or talc that people want to buy.  Mine owners take the ore out so that the land is protected and they still end up with sellable ore.  After it is mined, it is sorted into different grades according to size and quality.  After that, talc is ground up and sold.  How it is used depends on how it is found—in large chunks, small chunks, or softer kinds.  Click here for more detailed mining information. Talc is mined all over the world.  Some examples are:  The United States [California, Texas], Germany, Austria, South Africa, and Scotland.

  • What is it used for?  Talc is used for electrical and scientific products because it resists heat, electricity, and acid.  It is used in paints, rubber, insecticides, talcum powder, and paper.
Mineral Characteristic What the
mineralogists say		 Kid's Guide:  What it REALLY means!
Chemical Symbol H4Mg3Si4O10(OH)2

It has oxygen, silicon, magnesium, and hydrogen in it.
Color Colorless, white, pale green, or brown

These are the usual colors of the stone.
Streak White If you ground up a piece of talc, it would crush into white dust.
Transparency Translucent crystals, opaque masses If you look through a crystal of talc, it would look blurry.  Big pieces of talc cannot be seen through at all.
Luster Silky, waxy, pearly If you shine a light on talc, it will have a little reflection that will make it look silky or have a glow like pearls have.  It might have a waxy shine like candles.
Cleavage Perfect It will break smoothly along the same lines no matter how many times you break it.
Fracture Uneven When it is shattered, the pieces are uneven.
Magnetism None It will not attract, or be attracted to, a magnet.
Hardness 1 It is very soft.  You can scratch into it with a fingernail.
Specific gravity 2.7 – 2.8 Talc has about an average weight.  If you picked it up, it would not appear to be heavy or light for its size.
Crystal Shape Monoclinic

Monoclinic crystal shape