Gemstone Cleavage Chart
One of the characteristics of crystals is that they have cleavage. Cleavage is the tendency of a crystal to break cleanly along distinct planes. Since most gemstones are crystals, cleavage is an issue that gem buyers as well as jewelers and gem cutters need to take into account.
Minerals can possess anywhere from one to five cleavage planes, and each plane is assigned a grade or rating that denotes the level of ease with which the crystal can be cleaved. Cleavage is categorized as perfect, good, indistinct, or "none" (in instances where a gemstone lacks any cleavage).
The following chart lists the cleavage ratings for many well known gemstones. You'll note that different members of the same species or family, such as quartz or beryl, have the same cleavage. That's because members of the same species have the same crystal structure.
See our feature article on gemstone cleavage for more information.
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