The pumice comes from Italy; and the pigment which gives "the plug" its color is cadmium sulfide.

浮石产自意大利，给“塞子”上色的颜料则是硫化铬。

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Cadmium ion mainly comes from industrial waste water discharged by electroplating, battery, alloy manufacturing, pigment, mining and refining process.

镉离子主要来源于电镀、电池、合金制造、颜料、采矿与选矿行业排放的工业废水。

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As a substitute of cadmium red and chrome red, is a match environment red pigment. Used in thermoplastic resin, thermosetting resin, alkyd resin, rubber, other polymer and cement, coating.

做为环境友好红色颜料，替代镉红及铬红。应用与热塑性树脂、热固性树脂、醇酸树脂、橡胶其他聚合物以及水泥、涂料等。

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The new work was begun during a conservation treatment in 2009, when conservators found that the yellows in Flowers In A Blue Vase - this time from a pigment called cadmium yellow - had turned greyish and cracked.

BBC: Van Gogh's Flowers In A Blue Vase damage seen in X-rays