Z –Sawables. Whole crystals. Maximal distortion ratio 1:1.5, minute growth layers and steps allowed.
1q: 1st quality. Loupe clean stones or near surface pinpoints that can be polished out.
2q: 2nd quality. Minute inclusions in any parts of a stone. Surface steps, broken corners, and near surface small cracks allowed. One minute internal characteristic combined with a growth layer on one face is typical.
3q: 3rd quality. Shape requirements are same. Minor steps, minor internal features. Examples: minor crack in one zone, surface steps + crack, 2-3 minor near surface inclusions, a crack parallel to face + inclusion with clean central part.
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