Gold costs were about $317 per troy ounce in 2007, but these can vary widely depending on mining type and ore quality; global mine production amounted to 2,471.1 tonnes. After initial production, gold is often subsequently refined industrially by the Wohlwill process which is based on electrolysis or by the Miller process, that is chlorination in the melt. The Wohlwill process results in higher purity, but is more complex and is only applied in small-scale installations. Other methods of assaying and purifying smaller amounts of gold include parting and inquartation as well as cupellation, or refining methods based on the dissolution
Four Ways to Forgiveness Four Ways to Forgiveness Four Ways to Forgiveness is a collection of four short stories and novellas by American writer Ursula K. Le Guin. All four stories are set in the future and deal with the planets Yeowe and Werel, both members of the Ekumen, a collective of planets used by Le Guin as part of the background for many novels and short stories in her Hainish Cycle. In 2017 it was reissued as an e-book, augmented with a fifth related story by Le Guin, as Five Ways to Forgiveness. The stories in the book are set on two planets