Mineral powders are good crystalline, and they break along the cleavage plane when they are comminuted, which cause the mineral powders have flat surfaces and sharp edge angles.

但是由于矿物晶体粉碎过程中表现出沿解理面解理破裂的强烈倾向，使得矿物粉体表面具有平整的解理面及尖锐的棱角。

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Mineral oil and a varnish are then applied, and the instrument is then hand-sanded down to a flat finish.

接着涂上矿物油和油漆，并且用手将乐器抛光，得到平滑的外观。

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