Crystal habit

From Conservapedia - Reading time: 1 min

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Crystal habit is the term used to identify the shape, size and appearance of a crystal's unique growth characteristics.

Standard terms[edit]

• Acicular
  • Needle-like, slender and/or tapered
• Anhedral
  • Poorly formed and distorted
• Banded
  • Narrow bands of differing colors
• Bladed
  • Slender, flattened and blade-like
• Columnar
  • Long, slender prisms and parallel growth
• Dendritic
  • Tree-like multi-directional branching from central point
• Dodecahedral
  • 12-sided dodecahedron
• Drusy (also called Encrusted)
  • Aggregate of minute crystals coating a surface
• Enantiomorphic
  • Mirror-image (left/right) habit and optical characteristics
• Equant (also called Stubby)
  • Squashed, pinnacoids dominant over prisms
• Euhedral
  • Well-formed and undistorted
• Foliated
  • Easily separated into plates
• Geode
  • Rock cavities with internal crystals & encrustation
• Granular Mass
  • Anhedral crystals in lumpy mass with no crystal form
• Mamillary
  • Intersecting large rounded contours
• Massive
  • Shapeless with no distinct external crystal shape
• Octahedral
  • 8-sided octahedron - two pyramids, base to base
• Pincoid
  • Terminated by multiple pyramidal faces
• Prismatic
  • Elongated and prism-Like, all faces are parallel to c-axis
• Pseudomorphous
  • Occurring in the shape of another mineral
• Striated
  • Surface growth lines parallel or perpendicular to c-axis
• Tabular (also called Lamellar)
  • Flat, tablet-shaped, prominent pinnacoid