The gold, its alloys, and other metals, used by dentists / by James Robinson.

  • Robinson, James, 1813-1862.
Date:
1851
Catalogue details

Licence: Public Domain Mark

Credit: The gold, its alloys, and other metals, used by dentists / by James Robinson. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    contains about one-twelfth of its weight of copper, or copper and silver; the hardness is increased by this admixture, without ma- terially detracting from its malleability and duetility. The alloy with silver is tougher than that with eopper. If the gold used by dentists was alloyed in the same proportion as that of our coinage, it would be too soft for its intended purposes, and would soon lose its shape; still more so if alloyed with silver, independently of the colour being paler than that associated with gold in the public mind. The gold employed by re- spectable practitioners for making plates, is never less than 18 carats pure, but more frequently nearly 19 ; which means that 24 parts of the alloy contain 18 parts of pure gold, with 6 of silver or copper. Platinum is not much used for plates, owing probably to the difficulty of procuring it pure, and to its colour. Palladium is not often employed on account of its colour, and the action of c 2