Cleavage

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Cleavage in Minerals

Definition

If a mineral is strained beyond its elastic limits, it will break. If it breaks irregularly then it shows fracture, if it breaks along regular surfaces related to the crystal structure then it shows cleavage. This cleavage depends on weaknesses in the crystalline make-up of the mineral and is a diagnostic property which can reveal additional information about the mineral.

Table of Cleavage Types Used in this Database

Cleavage	Cleavage Description
Unknown	Mineral too small to observe cleavage.
None	No cleavage.
Very Good	Very good cleavage
Perfect	Very good, shiny cleavage surface.
Imperfect	Not perfect, equivalent to fair or good.
Good	Good, distinct cleavage surface.
Distinct	Distinct, recognizable cleavage surface.
Indistinct	Poorly formed cleavage surface.
Fair	Fair, recognizable cleavage surface.
Poor	Poorly formed cleavage surface.
Parting	Developed only in some specimens.

For Further Information on Cleavage

Search the Mineralogy Database

Example Subject Searches

Example: cleavage perfect finds all minerals with perfect cleavage.
Example: "cleavage-00*" finds all minerals a basal cleavage.

Cleavage in Minerals

Cleavage in Minerals

Definition

Table of Cleavage Types Used in this Database

For Further Information on Cleavage

Search the Mineralogy Database

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