Gold chalcogenides are compounds formed between

gold Gold is a chemical element with the symbol Au (from la, aurum) and atomic number 79. This makes it one of the higher atomic number elements that occur naturally. It is a bright, slightly orange-yellow, dense, soft, malleable, and ductile me ...

and one of the

chalcogen The chalcogens (ore forming) ( ) are the chemical elements in group 16 of the periodic table. This group is also known as the oxygen family. Group 16 consists of the elements oxygen (O), sulfur (S), selenium (Se), tellurium (Te), and the radioac ...

s, elements from

group 16 The chalcogens (ore forming) ( ) are the chemical elements in group 16 of the periodic table. This group is also known as the oxygen family. Group 16 consists of the elements oxygen (O), sulfur (S), selenium (Se), tellurium (Te), and the radioa ...

of the periodic table:

oxygen Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as ...

, sulfur,

selenium Selenium is a chemical element with the symbol Se and atomic number 34. It is a nonmetal (more rarely considered a metalloid) with properties that are intermediate between the elements above and below in the periodic table, sulfur and tellurium, ...

, or

tellurium Tellurium is a chemical element with the symbol Te and atomic number 52. It is a brittle, mildly toxic, rare, silver-white metalloid. Tellurium is chemically related to selenium and sulfur, all three of which are chalcogens. It is occasionall ...

. * Gold(III) oxide, Au₂O₃. Decomposes into gold and oxygen above 160 °C, and dissolves in concentrated alkalis to form solutions which probably contain the u(OH)₄sup>− ion *

Gold(I) sulfide Gold(I) sulfide is the inorganic compound with the formula . It is the principal sulfide of gold. It decomposes to gold metal and elemental sulfur, illustrating the "nobility" of gold. Structure and preparation The compound crystallizes in the mot ...

, Au₂S. Formed by passing hydrogen sulfide through solutions of gold(I) compounds. *

Gold(III) sulfide Gold(III) sulfide or auric sulfide is an inorganic compound with the formula .Auric sulfide has been described as a black and amorphous. Little evidence has been published supporting the existence of macroscopic quantities of this material. Clai ...

, Au₂S₃, unstable in the presence of water. *Gold tellurides: Au₂Te₃, Au₃Te₅, and AuTe₂ (approximate formulæ) are known as

non-stoichiometric compound In chemistry, non-stoichiometric compounds are chemical compounds, almost always solid inorganic compounds, having elemental composition whose proportions cannot be represented by a ratio of small natural numbers (i.e. an empirical formula); m ...

s. They show metallic conductivity. One telluride of gold is a superconductor at very low temperatures: Au₃Te₅ (1.62 K). Natural gold tellurides, like

calaverite Calaverite, or gold telluride, is an uncommon telluride of gold, a metallic mineral with the chemical formula AuTe2, with approximately 3% of the gold replaced by silver. It was first discovered in Calaveras County, California in 1861, and was ...

and

krennerite Krennerite is an orthorhombic gold telluride mineral which can contain variable amounts of silver in the structure. The formula is AuTe2, but specimen with gold substituted by up to 24% with silver have been found ( u0.77Ag0.24e2). Both of the c ...

(AuTe₂),

petzite The mineral petzite, Ag3 Au Te2, is a soft, steel-gray telluride mineral generally deposited by hydrothermal activity. It forms isometric crystals, and is usually associated with rare tellurium and gold minerals, often with silver, mercury, ...

( Ag₃AuTe₂), and sylvanite (AgAuTe₄), are minor ores of gold (and tellurium). See

telluride mineral A telluride mineral is a mineral that has the telluride anion as a main component. Tellurides are similar to sulfides and are grouped with them in both the Dana and Strunz mineral classification systems.http://webmineral.com/strunz/II.shtml Webm ...

s for more information on individual naturally occurring tellurides.

References

* Gold compounds Non-stoichiometric compounds Sulfides Tellurides {{inorganic-compound-stub Transition metal oxides