Wohlwill process Wohlwill process The Wohlwill process is an industrial-scale chemical procedure used to refine gold to the highest degree of purity (99.999%). The process was invented in 1874 by Emil Wohlwill. This electrochemical process involves using a cast gold ingot, often called a Doré bar, of 95%+ gold to serve as an anode. Lower percentages of gold in the anode will interfere with the reaction, especially when the contaminating metal is silver or one of the platinum group elements. The cathode(s) for this reaction are small sheets of pure (24k) gold sheeting or stainless steel. Current is applied to the system,
Purity and Danger Purity and Danger Purity and Danger: An Analysis of Concepts of Pollution and Taboo is a 1966 book by the anthropologist and cultural theorist Mary Douglas. It is her best known work. In 1991 the "Times Literary Supplement" listed it as one of the hundred most influential non-fiction books published since 1945. It has gone through numerous reprints and re-editions (1969, 1970, 1978, 1984, 1991, 2002). In 2003 a further edition was brought out as volume 2 in "Mary Douglas: Collected Works" (). The line of inquiry in "Purity and Danger" traces the words and meaning of dirt in different