Rock & Mineral Library

70 common rocks, minerals and gems with photos, key properties and practical tips for telling them apart.

Minerals

Agate

Hardness 6.5–7

Amethyst

Hardness 7

Apatite

Hardness 5

Aragonite

Hardness 3.5–4

Azurite

Hardness 3.5–4

Barite

Hardness 3–3.5

Beryl

Hardness 7.5–8

Biotite

Hardness 2.5–3

Calcite

Hardness 3

Celestine

Hardness 3–3.5

Chalcopyrite

Hardness 3.5–4

Cinnabar

Hardness 2–2.5

Corundum

Hardness 9

Diamond

Hardness 10

Dolomite

Hardness 3.5–4

Epidote

Hardness 6–7

Fluorite

Hardness 4

Galena

Hardness 2.5–2.75

Garnet

Hardness 7–7.5

Gold

Hardness 2.5–3

Gypsum

Hardness 2

Halite

Hardness 2–2.5

Hematite

Hardness 5.5–6.5

Jasper

Hardness 6.5–7

Kyanite

Hardness 4.5–7

Labradorite

Hardness 6–6.5

Magnetite

Hardness 5.5–6.5

Malachite

Hardness 3.5–4

Muscovite

Hardness 2–2.5

Native Copper

Hardness 2.5–3

Olivine

Hardness 6.5–7

Orthoclase

Hardness 6

Pyrite

Hardness 6–6.5

Quartz

Hardness 7

Rhodochrosite

Hardness 3.5–4

Rose Quartz

Hardness 7

Sodalite

Hardness 5.5–6

Sphalerite

Hardness 3.5–4

Staurolite

Hardness 7–7.5

Sulfur

Hardness 1.5–2.5

Talc

Hardness 1

Topaz

Hardness 8

Tourmaline

Hardness 7–7.5

Turquoise

Hardness 5–6

Mineraloids

Amber

Hardness 2–2.5

Opal

Hardness 5.5–6.5

Igneous rocks

Andesite

Hardness 6

Basalt

Hardness 6

Diorite

Hardness 6

Gabbro

Hardness 6–6.5

Granite

Hardness 6–7

Obsidian

Hardness 5–5.5

Pumice

Hardness 5.5–6

Rhyolite

Hardness 6–6.5

Scoria

Hardness 5.5–6

Sedimentary rocks

Breccia

Hardness 5–7

Chalk

Hardness 2–3

Chert

Hardness 6.5–7

Coal

Hardness 2–3

Conglomerate

Hardness 5–7

Limestone

Hardness 3–4

Sandstone

Hardness 6–7

Shale

Hardness 3

Metamorphic rocks

Gneiss

Hardness 6–7

Lapis Lazuli

Hardness 5–5.5

Marble

Hardness 3–4

Quartzite

Hardness 7

Schist

Hardness 4–5

Slate

Hardness 3–4

Soapstone

Hardness 1–2.5