Blowpipe Practice —— An Outline of Blowpipe Manipulation and Analysis, With Origin Tables, for the Determination of All Known Minerals

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ISBN: 9781331941064 出版年：2016 页码：299 E J Chapman Forgotten Books

P. 33, line 9: — after the solution has a distinct reddish-purple colour, add, and imparts a dark stain to metallic Silver or lead test-paper, in the manner of a sulphur or selenium compound.