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Browse by Property

Filter the whole catalogue the way mineralogists do — by structure, hardness, chemistry, or color.

Crystal systems seven symmetries

Cubic

Highest symmetry; three equal axes at 90°.

Trigonal

One 3-fold axis.

Amorphous

No long-range crystal structure.

Hexagonal

One 6-fold axis.

Triclinic

No axes at 90°; lowest symmetry.

Monoclinic

One oblique angle between axes.

Tetragonal

One 4-fold axis; two equal horizontal axes.

Orthorhombic

Three unequal axes, all at 90°.

Mohs hardness scratch scale 1–10 · the full scale →

1talc107 2gypsum692 3calcite1141 4fluorite846 5apatite804 6orthoclase599 7quartz241 8topaz68 9corundum16 10diamond5

Chemical class what it’s made of

Oxides & Hydroxides

Metal + oxygen or hydroxyl (OH).

Borates

Contain boron-oxygen groups.

Halides

Metal + halogen (Cl, F, Br, I); includes oxyhalides.

Iodates

Contain the IO₃ group.

Nitrates

Contain the NO₃ group.

Organic Minerals

Carbon-based mineral species (oxalates, hydrocarbons, resins).

Sulfates

Contain the SO₄ group.

Sulfides

Metal + sulfur; includes arsenides, selenides and tellurides.

Arsenates

Contain the AsO₄ group.

Chromates

Contain the CrO₄ group.

Silicates

Built on the SiO₄ tetrahedron; the largest class.

Vanadates

Contain the VO₄ group.

Carbonates

Contain the CO₃ group.

Molybdates

Contain the MoO₄ group.

Phosphates

Contain the PO₄ group.

Sulfosalts

Complex sulfides with semimetals (As, Sb, Bi).

Tungstates

Contain the WO₄ group.

Native Elements

Single elements and alloys; includes carbides, nitrides and phosphides.

Color what it looks like

Red

Blue

Gray

Pink

Black

Brown

Green

White

Orange

Purple

Yellow

Colorless