Since all forms of potassium alum are soluble in water, when the stone is wet or applied to wet skin, an invisible, fine layer of the mineral is rubbed off the stone and applied to the skins surface.

因为各种状态的钾明矾都能溶于水，当把它弄湿或接触湿皮肤时，会有一层肉眼看不见的细腻矿物层从钾明矾表面脱落，吸附到皮肤表面。

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Natural SiO2 of mineral water can form a layer of protection membrane on the surface of the skin.

活泉中含有的天然二氧化硅能在肌肤表面形成一层可透气的保护膜。

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It do not dissolve in the water, can in the skin surface Become a the layer shields, preventing the of water is lost.

它不溶于水，可在皮肤表面形成一层屏障，防止水份散失。

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