SnCl4; a fuming liquid (fuming spirit of Libavius), specific gravity 2.23, boiling point 115°C, that forms several hydrates; the pentahydrate (butter of tin) is used for mordanting and “loading” or “weighting” silk.
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a caustic liquid used as a mordant in dyemaking and for various other purposes; it is toxic and corrosive if inhaled or spilled on the skin.Medical dictionary. 2011.