Crystal Habit - List of Crystal Habits

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

Read more about this topic:  Crystal Habit

Famous quotes containing the words list of, list, crystal and/or habits:

    Religious literature has eminent examples, and if we run over our private list of poets, critics, philanthropists and philosophers, we shall find them infected with this dropsy and elephantiasis, which we ought to have tapped.
    Ralph Waldo Emerson (1803–1882)

    I am opposed to writing about the private lives of living authors and psychoanalyzing them while they are alive. Criticism is getting all mixed up with a combination of the Junior F.B.I.- men, discards from Freud and Jung and a sort of Columnist peep- hole and missing laundry list school.... Every young English professor sees gold in them dirty sheets now. Imagine what they can do with the soiled sheets of four legal beds by the same writer and you can see why their tongues are slavering.
    Ernest Hemingway (1899–1961)

    In a few days I’ll have lived one score and three days in this vale of tears. On I plod—always bored, often drunk, doing no penance for my faults—rather do I become more tolerant of myself from day to day, hardening my crystal heart with blasphemous humor and shunning only toothpicks, pathos, and poverty as being the three unforgivable things in life.
    F. Scott Fitzgerald (1896–1940)

    ... a nation to be strong, must be united; to be united, must be equal in condition; to be equal in condition, must be similar in habits and feeling; to be similar in habits and feeling, must be raised in national institutions as the children of a common family, and citizens of a common country.
    Frances Wright (1795–1852)