Iron sulfate

Iron sulfate may refer to:


An alum () is a type of chemical compound, usually a hydrated double sulfate salt of aluminium with the general formula XAl(SO4)2·12H2O, where X is a monovalent cation such as potassium or ammonium. By itself, "alum" often refers to potassium alum, with the formula KAl(SO4)2·12H2O. Other alums are named after the monovalent ion, such as sodium alum and ammonium alum.

The name "alum" is also used, more generally, for salts with the same formula and structure, except that aluminium is replaced by another trivalent metal ion like chromium(III), and/or sulfur is replaced by other chalcogen like selenium. The most common of these analogs is chrome alum KCr(SO4)2·12H2O.

In most industries, the name "alum" (or "papermaker's alum") is used to refer to aluminium sulfate Al2(SO4)3·nH2O, which is used for most industrial flocculation. In medicine, "alum" may also refer to aluminium hydroxide gel used as a vaccine adjuvant.


Aluminocopiapite is an aluminum iron sulfate mineral with the chemical formula Al2/3Fe3+4(SO4)6(OH)2·20H2O. Its type localties are Fortymile River in Alaska and the San Rafael Swell in Utah.


Alunite is a hydrated aluminium potassium sulfate mineral, formula KAl3(SO4)2(OH)6. It was first observed in the 15th century at Tolfa, near Rome, where it is mined for the manufacture of alum. First called aluminilite by J.C. Delamétherie in 1797, this name was contracted by François Beudant three decades later to alunite.Alunite crystals morphologically are rhombohedra with interfacial angles of 90° 50', causing them to resemble cubes. Crystal symmetry is trigonal. Minute glistening crystals have also been found loose in cavities in altered rhyolite. Alunite varies in color from white to yellow gray. The hardness is 4 and the specific gravity is between 2.6 and 2.8. It is insoluble in water or weak acids, but soluble in sulfuric acid.Sodium can substitute for potassium in the mineral, and when the sodium content is high, is called natroalunite.

Alunite is an analog of Jarosite, where aluminium replaces Fe3+. Alunite occurs as a secondary mineral on iron sulfate ores.

Alunite occurs as veins and replacement masses in trachyte, rhyolite, and similar potassium rich volcanic rocks. It is formed by the action of sulfuric acid bearing solutions on these rocks during the oxidation and leaching of metal sulfide deposits. Alunite also is found near volcanic fumaroles. The white, finely granular masses closely resemble finely granular limestone, dolomite, anhydrite, and magnesite in appearance. The more compact kinds from Hungary are so hard and tough that they have been used for millstones.Historically extensive deposits were mined in Tuscany and Hungary, and at Bulahdelah, New South Wales, Australia. It is currently mined at Tolfa, Italy. In the United States it is found in the San Juan district of Colorado; Goldfield, Nevada; the ghost town of Alunite, Utah near Marysvale; and Red Mountain near Patagonia, Arizona. The Arizona occurrence lies appropriately above a canyon named Alum Gulch. Alunite is mined as an ore of both potassium and aluminium at Marysvale. Some of the ore deposits were located by airborne and satellite multispectral imaging.

Archeology magazine May/June 2019 article states that in China, in Henan province, an assortment of ceramic objects and jars were found, dating back 2000 years. In one of the jars, a mixture of alunite and potassium nitrate was found. The mixture was then thought to be a "mixture of immortality" mentioned in ancient Chinese texts, obviously, does not appear to have succeeded.

Ammonium iron(II) sulfate

Ammonium iron(II) sulfate, or Mohr's salt, is the inorganic compound with the formula (NH4)2Fe(SO4)2·6H2O. Containing two different cations, Fe2+ and NH4+, it is classified as a double salt of ferrous sulfate and ammonium sulfate. It is a common laboratory reagent because it is readily crystallized, and crystals resist oxidation by air. Like the other ferrous sulfate salts, ferrous ammonium sulfate dissolves in water to give the aquo complex [Fe(H2O)6]2+, which has octahedral molecular geometry. Its mineral form is mohrite.


Argentojarosite is an iron sulfate mineral with the chemical formula AgFe3+3(SO4)2(OH)6. Its type locality is the East Tintic Mountains, Utah.

Banksia 'Giant Candles'

Banksia 'Giant Candles' is a registered Banksia cultivar. It is a hybrid between the Gosford form of B. ericifolia (heath-leaved banksia) and a form of B. spinulosa var. cunninghamii.

It looks like a shrub, and this form, that is equally broad as tall, can grow up to 5 metres. It is well known for its extremely large flower spikes, which easily can become 40 cm long. They have a habit of drooping or bending occasionally. The flowers are a bronzy-orange and will be showy from late autumn through winter.

They grow in most well-drained soils, and will flower best if grown in full sun. In an ideal area, they will grow up to 800 mm per year. In areas where irrigation is limited, they will not produce a heavy canopy, but will produce about 30% shade under its evergreen foliage.Russell Costin of Limpinwood Nursery, who originally propagated and registered it in the 1970s, has reported its popularity waned for a few years but has become more popular in the last decade. Angus Stewart reported it to be iron hungry, so treat yellowing with iron chelate or iron sulfate.

Banksia 'Yellow Wing' is a hybrid derived from Banksia Giant Candles and Banksia spinulosa var. collina.


Bílinite (Fe2+Fe23+(SO4)·22H2O) is an iron sulfate mineral. It is a product of the oxidation of pyrite in water. It is an acidic mineral that has a pH of less than 3 and is harmful to the environment when it comes from acid rock drainage (Keith et al., 2001).

Bílinite was first discovered near Bílina, Czech Republic which is why the mineral was named 'bílinite' (Palache, et al., 1969). This mineral possibly occurs on Mars.


Chaidamuite is a rare zinc – iron sulfate mineral with chemical formula: ZnFe3+(SO4)2(OH)·4H2O.

It was first described for an occurrence in the Xitieshan mine south of Mt. Qilianshan in the Chaidamu basin, Qinghai Province, China and was named for the locality. It occurs as an oxidation phase in a lead zinc deposit. In the type locality it is associated with the rare minerals: coquimbite, copiapite, butlerite and zincobotryogen. In addition to the Chinese occurrence it has been reported from the Getchell Mine in the Potosi District in Humboldt County, Nevada.


Copiapite is a hydrated iron sulfate mineral with formula: Fe2+Fe3+4(SO4)6(OH)2·20(H2O). Copiapite can also refer to a mineral group, the copiapite group.

Copiapite is strictly a secondary mineral forming from the weathering or oxidation of iron sulfide minerals or sulfide-rich coal. Its most common occurrence is as the end member mineral from the rapid oxidation of pyrite. It also occurs rarely with fumaroles. It occurs with melanterite, alunogen, fibroferrite, halotrichite, botryogen, butlerite and amarantite. It is by far the most common mineral in the copiapite group.

It rarely occurs as single crystals, is in the triclinic crystal system, and is pale to bright yellow. It is soluble in water, changing the water color to deep orange or orangish-red. In solution copiapite is very acidic. In high concentrations a negative pH can occur, as reported in waters draining from Richmond Mine at Iron Mountain, California. Copiapite can easily be distinguished from native sulfur because it does not give off an odor when dissolved in water. It can be distinguished from similar appearing uranium minerals, such as carnotite, by its lack of radioactivity. The only way to differentiate between the minerals in the copiapite group is by X-ray diffraction.

Copiapite was first described in 1833 for an occurrence near Copiapó, Atacama, Chile. It is sometimes known as yellow copperas. Other occurrences are in California, Nevada, and in the filled paleo sinkholes and caves of Missouri.

Copperas works

Copperas works were where copperas, Iron(II) sulfate, was produced from pyrite in coal and iron. The history of producing green vitriol, as it was known, goes back hundreds of years in Scotland. In 1814 Steubenville, Ohio had 7 copperas producing manufacturers.Pyrite has been used since classical times to manufacture copperas (iron(II) sulfate). Iron pyrite was heaped up and allowed to weather (an example of an early form of heap leaching). The acidic runoff from the heap was then boiled with iron to produce iron sulfate.The vitriolic waters of Fahlun (Falun) afford annually about 600 quintals of green vitriol (sulphate of iron), and a small quantity of blue vitriol (sulphate of copper).

Czapek medium

Czapek medium, also called Czapek's agar (CZA) or Czapek-Dox medium, is a growth medium for propagating fungi and other organisms in a laboratory. It was named after its inventors, Polish botanist Friedrich Johann Franz Czapek (May 16, 1868 - July 31, 1921) and American chemist Arthur Wayland Dox (September 19, 1882 - 1954). It was developed to grow Aspergillus niger and Penicillium camemberti. It works well for many saprophytic fungi and soil bacteria such as species of Aspergillus, Candida, Penicillium, and Paecilomyces.

Friedrich Czapek's original recipe is as follows:

1000 g distilled water

30 g cane sugar – energy source and sole source of carbon

1 g monopotassium phosphate – buffering agent

0.5 g magnesium sulfate – source of cations

0.5 g potassium chloride – source of essential ions

0.01 g iron sulfate – source of cations

Arthur Wayland Dox added 2 g of sodium nitrate in his version, to provide a sole source of nitrogen that is inorganic. This makes the medium a selective growth medium as only organisms that can use inorganic nitrogen can grow. Czapek and Dox did not add agar but many recipes add 15 g to make a solid medium.

Heap leaching

Heap leaching is an industrial mining process used to extract precious metals, copper, uranium, and other compounds from ore using a series of chemical reactions that absorb specific minerals and re-separate them after their division from other earth materials. Similar to in situ mining, heap leach mining differs in that it places ore on a liner, then adds the chemicals via drip systems to the ore, whereas in situ mining lacks these liners and pulls pregnant solution up to obtain the minerals. Most mining companies favor the economic feasibility of heap leaching, considering that heap leaching is a better alternative to conventional processing methods such as such as flotation, agitation, and vat leaching.Additionally, dump leaching is an essential part of most copper mining operations and determines the quality grade of the produced material along with other factors. Due to the profitability that the dump leaching has on the mining process, i.e. it can contribute substantially to the economic viability of the mining process, it is advantageous to include the results of the leaching operation in the economic overall project evaluation. This, in effect, requires that the key controllable variables, which have an effect on the recovery of the metal and the quality of solution coming from a dump leaching process.The process has ancient origins; one of the classical methods for the manufacture of copperas (iron sulfate) was to heap up iron pyrite and collect the leachate from the heap, which was then boiled with iron to produce iron(II) sulfate.

Iron polymaltose

Iron(III)-hydroxide polymaltose complex is a medication used to treat iron deficiency / iron deficiency anemia and belongs to the group of oral iron preparations. The preparation is a macromolecular complex, consisting of iron(III)-hydroxide (trivalent iron, Fe3+) and the carrier polymaltose and is available in solid form as a film-coated or chewable tablet and in liquid form as a syrup, drinkable solution, or drops. It is used for treating iron deficiency without anemia (latent iron deficiency) or with anemia (apparent iron deficiency). Prior to administration, the iron deficiency should be diagnostically established and verified via laboratory tests (e.g., low ferritin concentration, low transferrin saturation).

The drug has been on the market since 1978 and is approved in over 85 countries. In many countries it is known with brand name Maltofer(R).


Jarosite is a basic hydrous sulfate of potassium and iron with a chemical formula of KFe3+3(OH)6(SO4)2. This sulfate mineral is formed in ore deposits by the oxidation of iron sulfides. Jarosite is often produced as a byproduct during the purification and refining of zinc and is also commonly associated with acid mine drainage and acid sulfate soil environments.

Pressure oxidation

Pressure Oxidation is a process for extracting gold from refractory ore.

The most common refractory ores are pyrite and arsenopyrite, which are sulfide ores that trap the gold within them. Refractory ores require pre-treatment before the gold can be adequately extracted. The pressure oxidation process is used to prepare such ores for conventional gold extraction processes such as cyanidation. It is performed in an autoclave at high pressure and temperature, where high-purity oxygen mixes with a slurry of ore.When the original sulfide minerals are oxidized at high temperature and pressure, it completely releases the trapped gold. Pressure oxidation has a very high gold recovery rate, normally at least 10% higher than roasting.The oxidation of the iron sulfide minerals produces sulfuric acid, soluble compounds such as ferric sulfate, and solids such as iron sulfate or jarosite. The iron-based solids produced pose an environmental challenge, as they can release acid and heavy metals to the environment. They can also make later precious metal recovery more difficult. Arsenic in the ore is converted to solid scorodite inside the autoclave, allowing it to be easily disposed of. This is an advantage over processes such as roasting where these toxic products are released as gases.A disadvantage of pressure oxidation is that any silver in the feed material will often react to form silver jarosite inside the autoclave, making it difficult and expensive to recover the silver.An example of a mine utilizing this technology is the Pueblo Viejo mine in the Dominican Republic. At Pueblo Viejo, the process is performed by injecting high-purity oxygen into autoclaves operating at 230 degrees C and 40 bar of pressure. The resulting chemical reactions oxides the sulfide minerals the gold is trapped within. The oxidation of pyrite is highly exothermic, allowing the autoclave to operate at this temperature without an external heat source.


Quenstedtite is an uncommon iron sulfate mineral with chemical formula Fe2(SO4)3·11H2O. It forms violet or white triclinic crystals. Found in oxidized zones of pyrite-rich orebodies, especially in arid climates. It was first reported in 1888 for an occurrence in Tierra Amarilla, Copiapó Province, Atacama Region, Chile and named by G. Linck in 1889 for the German mineralogist F. A. von Quenstedt (1809–1889).


Rhomboclase is an acidic iron sulfate mineral with a formula reported as H5Fe3+O2(SO4)2·2(H2O) or HFe(SO4)2·4(H2O). It crystallizes in the orthorhombic system and typically occurs as tabular crystals with a rhombic outline. It occurs as transparent colorless, blue, green, yellow or grey crystals with a vitreous to pearly luster.Rhomboclase forms within the oxidizing environment of pyrite rich ore deposits and is reported as a post mine mineral of arid regions.It was first described in 1888 for an occurrence in Slovakia and was named from Latin, rhombus, rhomb, and Greek klasis, to break, for its crystal form and perfect basal cleavage.


Rozenite is a hydrous iron sulfate mineral, Fe2+SO4•4(H2O).

It occurs as a secondary mineral, formed under low humidity at less than 21 °C (70 °F) as an alteration of copper-free melanterite, which is a post mine alteration product of pyrite or marcasite. It also occurs in lacustrine sediments and coal seams. Associated minerals include melanterite, epsomite, jarosite, gypsum, sulfur, pyrite, marcasite and limonite.It was first described in 1960 for an occurrence on Ornak Mountain, Western Tatra Mountains, Małopolskie, Poland. It was named for Polish mineralogist Zygmunt Rozen (1874–1936).


Xitieshanite is a hydrous iron sulfate–chloride mineral with chemical formula: Fe3+(SO4)Cl·6(H2O).

It was discovered in 1983 and named for the discovery location of Xitieshan lead/zinc ore deposit in the Qinghai Province, China. The mineral has also been reported in 2005 from acid mine drainage from a coal mine in Green Valley, Vigo County, Indiana.


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