Silver assay. Historical engraving of an assayer and his assistant determining if a sample of silver contains gold. The assayer is standing in front o

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Silver assay. Historical engraving of an assayer and his assistant determining if a sample of silver contains gold. The assayer is standing in front of an assay furnace (A), while his assistant is weighing the alloy in water. Also labelled are the iron plate on to which the test sample was poured (B), a wooden eye-guard for observing the fire in the assay furnace (C) and a flask on a tripod for parting the sample of gold (D). Taken from The Laws of Art and Nature, in Knowing, Judging, Assaying, Fining, Refining and Inlarging the Bodies of Confin'd Metals (1863), John Pettus, a translation of the work of Lazarus Erckern.

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Size: 3582px × 4937px
Photo credit: © SHEILA TERRY/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

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