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MINERALS
Lesson 1 - Page 6

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A mineralís crystal form and how a mineral breaks is also helpful in determining a name. For example, if you see a shape that is long with 6 sides that form a point, you probably have a quartz crystal. However, if someone broke or fractured the crystal it would look like little pieces of broken glass.

The crystal form is the natural shape of that mineral if allowed to grow without restrictions. Finding crystals is not easy. The conditions have to be just right for crystals to grow.

Mineral tend to break in a characteristic pattern.  Fracture is irregular breakage, like quartz has a conchoidal fracture breaking along hollowed and rounded, uneven surfaces. Cleavage is a regular breakage that follows the atomic structure of a mineral. Cleavage results in smooth, flat surfaces. Different minerals may have one, two, three, four, or six cleavages. Calcite will break into perfect rhombohedrons 


Quartz crystal


Conchoidal fracture

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