These are graphite, high silicon cast iron, lead silver alloy, platinum, and even scrap steel rails.

所用材料有石墨、高硅铸铁、铅银合金、铂、甚至废钢轨等。

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A lead-base alloy enriched with silver and bismuth was obtained after separating silver and bismuth from crude lead with a continuous crystallizer.

粗铅采用连续结晶器分离银和铋后，得到一种富集银和铋的铅基合金。

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Niello: Black metallic alloy of sulfur with silver, copper, or lead, used to fill designs that have been engraved on the surface of a metal object, usually of silver.

黑金镶嵌：银、铜或铅的硫化黑色合金，用来镶嵌金属(通常是银)表面雕刻的图案。

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