Kieserite, or magnesium sulfate monohydrate, is a

hydrous In chemistry, a hydrate is a substance that contains water or its constituent elements. The chemical state of the water varies widely between different classes of hydrates, some of which were so labeled before their chemical structure was underst ...

magnesium sulfate Magnesium sulfate or magnesium sulphate (in English-speaking countries other than the US) is a chemical compound, a salt with the formula , consisting of magnesium cations (20.19% by mass) and sulfate anions . It is a white crystalline solid, ...

mineral with formula (MgSO₄·H₂O). It has a vitreous luster and it is colorless, grayish-white or yellowish. Its hardness is 3.5 and crystallizes in the

monoclinic In crystallography, the monoclinic crystal system is one of the seven crystal systems. A crystal system is described by three vectors. In the monoclinic system, the crystal is described by vectors of unequal lengths, as in the orthorhombic s ...

crystal system In crystallography, a crystal system is a set of point groups (a group of geometric symmetries with at least one fixed point). A lattice system is a set of Bravais lattices. Space groups are classified into crystal systems according to their po ...

Gunningite Gunningite is one of the minerals in the Kieserite group, with the chemical formula . Its name honours Henry Cecil Gunning (1901–1991) of the Geological Survey of Canada and a professor at the University of British Columbia. Occurrence Gunning ...

is the zinc member of the kieserite group of minerals.

Etymology

It is named after

Dietrich Georg von Kieser Dietrich Georg von Kieser (24 August 1779 – 11 October 1862) was a German physician born in Harburg. He studied medicine at the Universities of Würzburg and Göttingen, receiving his doctorate from the latter institution in 1804. For most of h ...

(Jena, Germany 1862)

Occurrence

Kieserite commonly occurs in marine

evaporite An evaporite () is a water-soluble sedimentary mineral deposit that results from concentration and crystallization by evaporation from an aqueous solution. There are two types of evaporite deposits: marine, which can also be described as ocea ...

s and rarely in

volcanic A volcano is a rupture in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface. On Earth, volcanoes are most often found where tectonic plates a ...

environments as a sublimate. It occurs in association with

halite Halite (), commonly known as rock salt, is a type of salt, the mineral (natural) form of sodium chloride ( Na Cl). Halite forms isometric crystals. The mineral is typically colorless or white, but may also be light blue, dark blue, purple, p ...

carnallite Carnallite (also carnalite) is an evaporite mineral, a hydrated potassium magnesium chloride with formula KMgCl3·6(H2O). It is variably colored yellow to white, reddish, and sometimes colorless or blue. It is usually massive to fibrous with rare ...

polyhalite Polyhalite is an evaporite mineral, a hydrated sulfate of potassium, calcium and magnesium with formula: . Polyhalite crystallizes in the triclinic system, although crystals are very rare. The normal habit is massive to fibrous. It is typically c ...

anhydrite Anhydrite, or anhydrous calcium sulfate, is a mineral with the chemical formula CaSO4. It is in the orthorhombic crystal system, with three directions of perfect cleavage parallel to the three planes of symmetry. It is not isomorphous with the ...

boracite Boracite is a magnesium borate mineral with formula: Mg3 B7 O13 Cl. It occurs as blue green, colorless, gray, yellow to white crystals in the orthorhombic - pyramidal crystal system. Boracite also shows pseudo-isometric cubical and octahedral fo ...

, sulfoborite,

leonite Leonite is a hydrated double sulfate of magnesium and potassium. It has the formula K2SO4·MgSO4·4H2O. The mineral was named after Leo Strippelmann, who was director of the salt works at Westeregeln in Germany. The mineral is part of the blodit ...

epsomite Epsomite, Epsom salt, or magnesium sulfate heptahydrate, is a hydrous magnesium sulfate mineral with formula MgSO4·7H2O. Epsomite crystallizes in the orthorhombic system as rarely found acicular or fibrous crystals, the normal form is as massi ...

and celestine.

Mars

In early 2005,

Mars Express ''Mars Express'' is a space exploration mission being conducted by the European Space Agency (ESA). The ''Mars Express'' mission is exploring the planet Mars, and is the first planetary mission attempted by the agency. "Express" originally ref ...

, a

European Space Agency , owners = , headquarters = Paris, Île-de-France, France , coordinates = , spaceport = Guiana Space Centre , seal = File:ESA emblem seal.png , seal_size = 130px , image = Views in the Main Control Room (1205 ...

orbiter, discovered evidence of kieserite in patches of

Valles Marineris Valles Marineris (; Latin for ''Mariner program, Mariner Valleys'', named after the ''Mariner 9'' Mars orbiter of 1971–72 which discovered it) is a system of canyons that runs along the Mars, Martian surface east of the Tharsis region. At more ...

(the largest canyon on

Mars Mars is the fourth planet from the Sun and the second-smallest planet in the Solar System, only being larger than Mercury (planet), Mercury. In the English language, Mars is named for the Mars (mythology), Roman god of war. Mars is a terr ...

), along with

gypsum Gypsum is a soft sulfate mineral composed of calcium sulfate dihydrate, with the chemical formula . It is widely mined and is used as a fertilizer and as the main constituent in many forms of plaster, blackboard or sidewalk chalk, and drywall. ...

and polyhydrated

sulfate The sulfate or sulphate ion is a polyatomic anion with the empirical formula . Salts, acid derivatives, and peroxides of sulfate are widely used in industry. Sulfates occur widely in everyday life. Sulfates are salts of sulfuric acid and many ar ...

s. This is direct evidence of Mars's watery past and augments similar discoveries made by the

Mars Exploration Rover NASA's Mars Exploration Rover (MER) mission was a robotic space mission involving two Mars rovers, ''Spirit (rover), Spirit'' and ''Opportunity (rover), Opportunity'', exploring the planet Mars. It began in 2003 with the launch of the two rover ...

Opportunity Opportunity may refer to: Places * Opportunity, Montana, an unincorporated community, United States * Opportunity, Nebraska, an unincorporated community, United States * Opportunity, Washington, a former census-designated place, United States * 3 ...

in 2004.

Moons of Jupiter

Kieserite might also be a rock-forming mineral in the icy mantle of the outer three

Galilean moons The Galilean moons (), or Galilean satellites, are the four largest moons of Jupiter: Io, Europa, Ganymede, and Callisto. They were first seen by Galileo Galilei in December 1609 or January 1610, and recognized by him as satellites of Jupiter ...

(

Europa Europa may refer to: Places * Europe * Europa (Roman province), a province within the Diocese of Thrace * Europa (Seville Metro), Seville, Spain; a station on the Seville Metro * Europa City, Paris, France; a planned development * Europa Cliff ...

, Ganymede,

Callisto Callisto most commonly refers to: *Callisto (mythology), a nymph *Callisto (moon), a moon of Jupiter Callisto may also refer to: Art and entertainment *''Callisto series'', a sequence of novels by Lin Carter *''Callisto'', a novel by Torsten Kro ...

). At pressures higher than 2.7

GPa Grading in education is the process of applying standardized measurements for varying levels of achievements in a course. Grades can be assigned as letters (usually A through F), as a range (for example, 1 to 6), as a percentage, or as a numbe ...

, kieserite transforms to a triclinic crystal structure.

Uses

It is used in the production of

Epsom salt Epsomite, Epsom salt, or magnesium sulfate heptahydrate, is a hydrous magnesium sulfate mineral with formula MgSO4·7H2O. Epsomite crystallizes in the orthorhombic system as rarely found acicular or fibrous crystals, the normal form is as massi ...

and as a fertilizer, the overall global annual usage in agriculture in the mid 1970s was 2.3 million tons. Kieserite crystal structure

Kieserite is also used for cleaning hard water deposits from tiles, stones, and other pool and fountain lining materials. Due to its hardness, which is greater than hard water deposits but less than tiles and other water feature linings, it is blasted at the hard water deposits to remove them.

When to use kieserite as a fertilizer

Response to Kieserite is likely where: • Soil Mg levels are low • pH is high • Intensive liming occurs to raise the pH • Nitrogen is applied as ammonium, as this can lead to an antagonism between ammonium and magnesium • Compacted soils exist • There is a period of wet/cold weather • Dry weather occurs leading to low magnesium mobility in the soil profile.

References

{{Reflist Magnesium minerals Sulfate minerals Monoclinic minerals Minerals in space group 15 Evaporite