Please forward this error screen to 104. Brown, dean of the College of Mines and Earth Sciences at the University of Utah, provides the following answer. The purity of gold is defined either in karats 24k gold fineness.
24 part of pure gold by weight, so 24-karat gold is pure gold. To find the percentage of gold in an object when the purity is stated in karats, multiply the number of karats by 100 and divide by 24. For example, 12-karat gold is 50 percent pure gold. Alternatively, the fineness is the amount of gold in parts per 1,000, so pure gold has a fineness of 1,000. Sign up for our email newsletter. Scientific American maintains a strict policy of editorial independence in reporting developments in science to our readers. 2018 Scientific American, a Division of Nature America, Inc.