List of Crystal Habits
Habit | Image | Description | Common Example(s) |
---|---|---|---|
Acicular | Needle-like, slender and/or tapered | Natrolite, Rutile | |
Amygdaloidal | Almond-shaped | Heulandite, subhedral Zircon | |
Bladed | Blade-like, slender and flattened | Actinolite, Kyanite | |
Botryoidal or globular | Grape-like, hemispherical masses | Hematite, Pyrite, Malachite, Smithsonite, Hemimorphite, Adamite, Variscite | |
Columnar | Similar to fibrous: Long, slender prisms often with parallel growth | Calcite, Gypsum/Selenite | |
Coxcomb | Aggregated flaky or tabular crystals closely spaced. | Barite, Marcasite | |
Cubic | Cube shape | Pyrite, Galena, Halite | |
Dendritic or arborescent | Tree-like, branching in one or more direction from central point | Pyrolusite and other Mn-oxide minerals, Magnesite, native copper | |
Dodecahedral | Dodecahedron, 12-sided | Garnet | |
Drusy or encrustation | Aggregate of minute crystals coating a surface or cavity | Uvarovite, Malachite, Azurite | |
Enantiomorphic | Mirror-image habit (i.e. crystal twinning) and optical characteristics; right- and left-handed crystals | Quartz, Plagioclase, Staurolite | |
Equant, stout | Length, width, and breadth roughly equal | Olivine, Garnet | |
Fibrous | Extremely slender prisms | Serpentine group, Tremolite (i.e. Asbestos) | |
Filiform or capillary | Hair-like or thread-like, extremely fine | many Zeolites | |
Foliated or micaceous or lamellar (layered) | Layered structure, parting into thin sheets | Mica (Muscovite, Biotite, etc.) | |
Granular | Aggregates of anhedral crystals in matrix | Bornite, Scheelite | |
Hemimorphic | Doubly terminated crystal with two differently shaped ends. | Hemimorphite, Elbaite | |
Hexagonal | Hexagon shape, six-sided | Quartz, Hanksite | |
Hopper crystals | Like cubic, but outer portions of cubes grow faster than inner portions, creating a concavity | Halite, Calcite, synthetic Bismuth | |
Mamillary | Breast-like: surface formed by intersecting partial spherical shapes, larger version of botryoidal, also concentric layered aggregates | Malachite, Hematite | |
Massive or compact | Shapeless, no distinctive external crystal shape | Limonite, Turquoise, Cinnabar, Realgar | |
Nodular or tuberose | Deposit of roughly spherical form with irregular protuberances | Chalcedony, various Geodes | |
Octahedral | Octahedron, eight-sided (two pyramids base to base) | Diamond, Magnetite | |
Plumose | Fine, feather-like scales | Aurichalcite, Boulangerite, Mottramite | |
Prismatic | Elongate, prism-like: crystal faces parallel to c-axis well-developed | Tourmaline, Beryl | |
Pseudo-hexagonal | Hexagonal appearance due to cyclic twinning | Aragonite, Chrysoberyl | |
Radiating or divergent | Radiating outward from a central point | Wavellite, Pyrite suns | |
Reniform or colloform | Similar to botryoidal/mamillary: intersecting kidney-shaped masses | Hematite, Pyrolusite, Greenockite | |
Reticulated | Crystals forming net-like intergrowths | Cerussite | |
Rosette or lenticular (lens shaped crystals) | Platy, radiating rose-like aggregate | Gypsum, Barite (i.e. Desert rose) | |
Sphenoid | Wedge-shaped | Sphene | |
Stalactitic | Forming as stalactites or stalagmites; cylindrical or cone-shaped | Calcite, Goethite | |
Stellate | Star-like, radiating | Pyrophyllite, Aragonite | |
Striated | Not a habit per se, but a condition of lines that can grow on certain crystal faces on certain minerals | Tourmaline, Pyrite, Quartz, Feldspar, Sphalerite | |
Stubby or blocky or tabular | More elongated than equant, slightly longer than wide, flat tablet shaped | Feldspar, Topaz | |
Platy | Flat, tablet-shaped, prominent pinnacoid | Wulfenite | |
Tetrahedral | Tetrahedra-shaped crystals | Tetrahedrite, Spinel, Magnetite | |
Wheat sheaf | Aggregates resembling hand-reaped wheat sheaves | Stilbite |
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