Gold sulfide is the inorganic compound

Inorganic compound

Inorganic compounds have traditionally been considered to be of inanimate, non-biological origin. In contrast, organic compounds have an explicit biological origin. However, over the past century, the classification of inorganic vs organic compounds has become less important to scientists,...

 with the formula Au₂S. It is one of two principal sulfide

Sulfide

A sulfide is an anion of sulfur in its lowest oxidation state of 2-. Sulfide is also a slightly archaic term for thioethers, a common type of organosulfur compound that are well known for their bad odors.- Properties :...

s of gold

Gold

Gold is a chemical element with the symbol Au and an atomic number of 79. Gold is a dense, soft, shiny, malleable and ductile metal. Pure gold has a bright yellow color and luster traditionally considered attractive, which it maintains without oxidizing in air or water. Chemically, gold is a...

. Gold sulfides exist in nature as solid solutions with silver, which has the same covalent radius.

Structure and preparation

The compound crystallizes in the motif seen for cuprous oxide: gold is 2-coordinate, sulfur four coordinate, and the S-Au-S linkage is linear. Linear coordination geometry is typically adopted by gold(I) compounds, such as the coordination complex chloro(dimethyl sulfide)gold(I)

Chloro(dimethyl sulfide)gold(I)

Chlorogold is an coordination complex of gold. It is a white solid. This compound is a common entry point into gold chemistry.-Structure:...

.

It can be prepared by treating gold chloride with hydrogen sulfide

Hydrogen sulfide

Hydrogen sulfide is the chemical compound with the formula . It is a colorless, very poisonous, flammable gas with the characteristic foul odor of expired eggs perceptible at concentrations as low as 0.00047 parts per million...

It also arises by treating dicyanoaurate:

H₂S + 2 KAu(CN)₂ → Au₂S + 2 KCN + 2 HCN

This product is described as "initially dark reddish-brown" solid that turns "steel-gray.”