Native Elements: Graphite

Composition: C

Crystal system: Hexagonal; commonly as scales, foliated masses or individual grains

3.4.1 graphite Mt Isa Qld Australia

Properties:

• Metallic to earthy lustre
• Black color
• Black streak; marks paper
• Fingernail scratches easily (Mohs Hardness 1-2)
• Low density
• Perfect single cleavage
• Cleaves rather than fractures
• Not ferromagnetic
• Does not react with hydrochloric acid (HCl)

Occurrence:

Graphite is formed mainly by the metamorphism of organic-rich sedimentary rocks including coals, but it can occur also as an accessory mineral in some igneous rocks and hydrothermal vein deposits .

Graphite has a range of industrial applications including the manufacture of so-called lead pencils.