conchoidal

  1. Adjective.  (mineralogy) Describing a type of irregular fracture that occurs in materials with no natural plane of separation, such as flint.
  2. Adjective.  (context, of the fracture of minerals and rocks) having smooth shell-shaped convex and concave surfaces.
  3. Adjective.  (context, of minerals and rocks, such as flint) having such a fracture.

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This entry was last updated on RefTopia from its source on 3/20/2012.