Silverwork and jewelry : a text-book for students and workers in metal (1912)
Wilson, H, Bisei, Unno · New York : D. Appleton · leaf 47
sufficient quantity has been gathered,the sweep should be burned in an irontray to remove any trace of organicmatter, the resulting ash well tried overwith a magnet to remove any bits of ironwire, and the sweep sent to the refiners,who, after making an assay, will allow forthe precious metal it may… … Fig. 3. 40
Silverwork · Jewelry
Internet Archive · New York Public Library · Public Domain Mark 1.0. Free to use for anything.
