A manual on dental metallurgy / by Ernest A. Smith.

  • Smith, Ernest A. (Ernest Alfred)
Date:
1903
Catalogue details

Licence: In copyright

Credit: A manual on dental metallurgy / by Ernest A. Smith. Source: Wellcome Collection.

Provider: This material has been provided by The University of Glasgow Library. The original may be consulted at The University of Glasgow Library.

    241/334 (page 221)
    most common impurities in commercial cop]ier are iron, arsenic, silver, and copper oxide, and occasionally bisnnitli, tin, antimony, snlphnr and lead. Of these arsenic, sulphur, and antimony are the most injurious, as they harden the metal and impair its malleability and tenacity. Molten copper has the property of dissolving copper oxide, which makes it more or less brittle. The effect of iron is to render copper harder and paler in colour. Bismuth lessens the toughness of the metal. Use in Dental Laboratory.—In the uncom- bined state copper has very little application in the dental laboratory, but when added in small quantities it forms a valuable constituent in alloys of gold and other metals, conferring upon them many useful properties. Alloys.—Copper unites easily with most other metals, and forms the basis of a large number of im- portant alloys. Copper and Gold.—When melted together these metals alloy in all proportions, and when the copper does not exceed lO to 12 per cent, the malleability is little altered—thus 21 carat gold and higher qualities are practically as malleable as pure gold. (See also Gold Alloys, p. 103.) Copper and Silver.—These metals combine in all proportions, the resulting alloys ranging in colour from the red of copper through yellowish tints to the white colour of silver. These metals form a series of most valuable alloys, having a great variety of applica- tions in the arts. (See also Silver Alloys, p. 17 i.) Copper and Zinc.—Copper unites readily with zinc, forming alloys generally known as brass.