Kieserite is a highly unstable magnesium sulfate

Magnesium sulfate

Magnesium sulfate is a chemical compound containing magnesium, sulfur and oxygen, with the formula MgSO4. It is often encountered as the heptahydrate epsomite , commonly called Epsom salt, from the town of Epsom in Surrey, England, where the salt was distilled from the springs that arise where the...

 mineral (MgSO₄·H₂O). It has a vitreous luster and it is colorless, grayish-white or yellowish. Its hardness is 3.5 and it has a monoclinic crystal system. It is used in the production of Epsom salt and is named after Dietrich Georg von Kieser

Dietrich Georg von Kieser

Dietrich Georg von Kieser 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 his career he was a professor at the University of Jena, where from 1824 to 1862 he served...

 (Jena, Germany 1862).

In early 2005, Mars Express

Mars Express

Mars Express is a space exploration mission being conducted by the European Space Agency . The Mars Express mission is exploring the planet Mars, and is the first planetary mission attempted by the agency. "Express" originally referred to the speed and efficiency with which the spacecraft was...

, a European Space Agency

European Space Agency

The European Space Agency , established in 1975, is an intergovernmental organisation dedicated to the exploration of space, currently with 18 member states...

 orbiter, discovered evidence of kieserite in patches of Valles Marineris

Valles Marineris

Valles Marineris is a system of canyons that runs along the Martian surface east of the Tharsis region...

 (the largest canyon on Mars

Mars

Mars is the fourth planet from the Sun in the Solar System. The planet is named after the Roman god of war, Mars. It is often described as the "Red Planet", as the iron oxide prevalent on its surface gives it a reddish appearance...

), along with gypsum

Gypsum

Gypsum is a very soft sulfate mineral composed of calcium sulfate dihydrate, with the chemical formula CaSO4·2H2O. It is found in alabaster, a decorative stone used in Ancient Egypt. It is the second softest mineral on the Mohs Hardness Scale...

 and polyhydrated sulfate

Sulfate

In inorganic chemistry, a sulfate is a salt of sulfuric acid.-Chemical properties:...

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

Mars Exploration Rover

NASA's Mars Exploration Rover Mission is an ongoing robotic space mission involving two rovers, Spirit and Opportunity, exploring the planet Mars...

 Opportunity

Opportunity rover

Opportunity, MER-B , is a robotic rover on the planet Mars, active since 2004. It is the remaining rover in NASA's ongoing Mars Exploration Rover Mission...

 in 2004.

Related minerals

• Gunningite
  Gunningite
  Gunningite is one of the minerals in the Kieserite group. Its chemical formula is SO4·H2O. Its name honours Henry Cecil Gunning of the Geological Survey of Canada and a Professor at the University of British Columbia, Vancouver, Canada....
  
   is the Zn-rich version of this mineral
• Epsomite
  Epsomite
  Epsomite is a hydrous magnesium sulfate mineral with formula MgSO4·7H2O or simply MgSO4. Epsomite forms as encrustations or efflorescences on limestone cavern walls and mine timbers and walls, as a volcanic fumaroles, and as rare beds in evaporate layers...
  
  is more hydrated version