Scientific analysis reveals that the colors were derived from ocher and other iron oxides ground into a fine powder.

科学分析表明，这些颜色是源自赭石和其他铁氧化物磨成的细粉。

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Exposed iron will gradually rust away to powder.

放在露天的铁会逐渐锈成粉末。

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Rapid spray painted sheet metal tips: extra demand note owners brothers dry corrosion, bird droppings, gum and iron powder in the paint.

快速钣金喷漆提示车主兄弟：旱季格外需求注意酸雨、鸟粪、树胶和铁粉对车漆的腐蚀。

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Oxygen generators contain sodium chlorate and iron powder -- solid chemicals that are mixed and cast into a solid shape.

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For instance, Nespray, an instant milk powder, contains calcium, zinc and iron all essential for children.

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The spray-on metal powder is 50% to 70% iron.

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