Iron Pyrite and its Properties
Hamza C¸ oban
(Dated: June 7, 2020)
HISTORY
Iron pyrite is an opaque and pale brass-yellow mineral, which strikes fire. Thus, the name pyrite is given from
the Greek pyrit¯es lithos ”stone or mineral which strikes fire” [1]. Pyrite is also called fool’s gold due to its physical
similarity to gold nuggets. Iron pyrite was first used in 300 CE for the production of sulfur in China’s Shanxi,
Hebei, Henan, Hunan, and Sichuan provinces. One of the earliest descriptions of the medicinal use of sulfur was in
The Pharmacopeia of the Heavenly Husbandsman, compiled in the Western Han period (206 BCE–24 CE), which
cataloged the medicines invented some 3,500 years earlier by the legendary emperor Shen Nong. Historically, pyrite
has been mined for sulfure and sulfuric acid production. However, nowadays it is mined mainly for paper industry
and battery production. Additionally, it was used as a source of ignition in the 16th 17th centuries [2].
MINING AND PRODUCTION
Iron pyrite is commonly found any geographical area from sedimentary deposits to hydro-thermal veins. It is found
with minor impurities from nickel, cobalt and arsenic. Iron pyrite is not preferred for iron production, since iron oxide
is a better alternative. Currently global pyrite production is about 14 million tons per year, and about 85 percent of
this is in China. Interestingly, United States does not have any pyrite mine. The US has shut down all pyrite mines
due to loss of interest of current economy. According to latest reports of MTA (Mineral Research and Exploration
General Directorate of Turkey) there is no operating pyrite mines in Turkey.
PHYSICAL PROPERTIES
The chemical formula of pyrite is FeS2and its molecular weight is 119.98 gr/mol. Its hardness is 6-6.5 in Mohs
scale. Its density is 5 gr/cm3. The crystal structure of pyrite is a simple cubic with lattice constant a= 5.417A°. The
unit cell contains 4 iron and 8 sulfure atoms the corresponding number of atoms in unit cell is 1.5.
