Dimorphite is a very rare orange-yellow chalcogenide

Chalcogenide

A chalcogenide is a chemical compound consisting of at least one chalcogen ion and at least one more electropositive element. Although all group 16 elements of the periodic table are defined as chalcogens, the term is more commonly reserved for sulfides, selenides, and tellurides, rather than...

 mineral. In nature, dimorphite forms primarily by deposit in volcanic fumaroles at temperatures of 70°-80°C (158°F-176°F). Dimorphite was first discovered in a such a fumarole near Naples, Italy in 1849 by the mineralologist Arcangelo Scacchi (1810-1893). Since its discovery, dimorphite has been found in the Alacrán silver mine near Copiapó

Copiapó

Copiapó is a city in northern Chile, located about 40 miles east of the coastal town of Caldera. Founded on December 8, 1744, it is the capital of Copiapó Province and Atacama Region....

, Chile

Chile

Chile ,officially the Republic of Chile , is a country in South America occupying a long, narrow coastal strip between the Andes mountains to the east and the Pacific Ocean to the west. It borders Peru to the north, Bolivia to the northeast, Argentina to the east, and the Drake Passage in the far...

. It has also been reported from Cerro de Pasco

Cerro de Pasco

Cerro de Pasco is a city in central Peru. It is the capital of the Pasco region, and an important mining center. It is connected by road and by rail to the city of Lima.- Overview :...

, Peru

Peru

Peru , officially the Republic of Peru , is a country in western South America. It is bordered on the north by Ecuador and Colombia, on the east by Brazil, on the southeast by Bolivia, on the south by Chile, and on the west by the Pacific Ocean....

, and the Lavrion District Mines in Attica

Attica

Attica is a historical region of Greece, containing Athens, the current capital of Greece. The historical region is centered on the Attic peninsula, which projects into the Aegean Sea...

, Greece

Greece

Greece , officially the Hellenic Republic , and historically Hellas or the Republic of Greece in English, is a country in southeastern Europe....

.

Properties and applications

Dimorphite has two crystal forms, Α- and Β-. This property gives rise to its name, which comes from the Greek for "two" and "form." Dimorphite transitions between its α- and β- forms at around 130°C (266°F).

Dimorphite can be synthesized by melting arsenic and sulfur together in the proper molar ratios in vacuum.

Initial research done by professors from the Technical University of Moldova

Technical University of Moldova

The Technical University of Moldova is a higher technical educational institution located in the Republic of Moldova, and is the only such institute in the country to be accredited by the state.-History:...

 and the Bundeswehr University of Munich indicates the possibility of using dimorphite in the development of gas sensors, due to the semiconductive properties of dimorphite.