Circular touchstone from the bazaar, Istanbul, 1987

Made:
1987
maker:
Unknown

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Science Museum Group
© The Board of Trustees of the Science Museum

Science Museum Group
© The Board of Trustees of the Science Museum

Science Museum Group
© The Board of Trustees of the Science Museum

Circular piece of touchstone bought in the bazaar in Istanbul. This had been imported from Belgium. Previous identifier: 1987-2

Touchstones are fine-grained siliceous stones, on whose abrasive surface a gold sample undergoing checks for purity would be rubbed. A streak of gold would be left on the stone’s surface, which could be compared against gold of known quality, to establish the sample’s purity. Touchstones were the main means of assaying the quality of gold throughout history, but remain in use today.

Details

Category:
Metallurgy
Object Number:
2019-82
type:
touchstone
credit:
Gift of Dr W.A. Oddy