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CRYSTAL HABITS CRYSTAL HABITS
HABIT DESCRIPTION EXAMPLE HABIT DESCRIPTION EXAMPLE
Acicular Needle-like, slender and/or Rutile in quartz Dodecahedral Dodecahedron, 12-sided Garnet
tapered
Amygdaloidal Almond-shaped Heulandite Drusy or Aggregate of minute crystals Uvarovite
encrustation coating a surface
Anhedral Poorly formed, external crystal Olivine Enantiomorphic Mirror-image habit and optical Quartz
faces not developed characteristics; right- and left-
handed crystals
Bladed Blade-like, slender and flattened Kyanite Equant, stout, Length, width, and breadth Zircon
stubby or blocky roughly equal
Botryoidal or Grape-like, hemispherical Smithsonite,Hemimorphit Euhedral Well-formed, external crystal Spinel
globular masses e,Adamite and Variscite faces developed
Columnar Stout, column-like individuals Calcite Fibrous or Extremely slender prisms Tremolite
columnar
Coxcomb Aggregated flaky or tabular Barite Filiform or Hair-like or thread-like, Natrolite
crystals closely spaced capillary extremely fine
Dendritic or Tree-like, branching in one or Magnesite in opal Foliated or Layered structure, parting into Mica
arborescent more direction from central point micaceous thin sheets
CRYSTAL HABITS CRYSTAL HABITS
HABIT DESCRIPTION EXAMPLE HABIT DESCRIPTION EXAMPLE
Granular Aggregates of anhedral crystals Scheelite Pseudo- hexagonal appearance due to Aragonite
in matrix hexagonal cyclic twinning
Hemimorphic Doubly terminated crystal with Hemimorphite Pseudomorphou Occurring in the shape of Tiger's eye
two differently shaped ends s another mineral through
pseudomorphous replacement
Mamillary Breast-like: surface formed by Malachite Radiating or Radiating outward from a central Pyrite suns
intersecting partial spherical divergent point
shapes
Massive or Shapeless, no distinctive Serpentine Reniform or Similar to mamillary: intersecting Hematite
compact external crystal shape colloform kidney-shaped masses
Nodular or Deposit of roughly spherical Geodes Reticulated Acicular crystals forming net-like Cerussite
tuberose form with irregular intergrowths
protuberances
Octahedral Octahedron, eight-sided (two Diamond Rosette Platy, radiating rose-like Gypsum
pyramids base to base) aggregate
Plumose Fine, feather-like scales Mottramite Sphenoid Wedge-shaped Sphene
Prismatic Elongate, prism-like: crystal Tourmaline Stalactitic Forming as stalactites or Rhodochrosite
faces parallel to c-axis well- stalagmites: cylindrical or cone-
developed shaped
19/04/2024
CRYSTAL HABITS
HABIT DESCRIPTION EXAMPLE
Stellate Star-like, radiating Pyrophyllite
Striated/striations Surface growth lines parallel or Chrysoberyl
perpendicular to a
crystallographic axis
Subhedral External crystal faces only
partially developed
Tabular or Flat, tablet-shaped, prominent Ruby
lamellar pinnacoid
Wheat sheaf Aggregates resembling hand- Zeolites
reaped wheat sheaves
