Epsomite

Epsomite^[1]^[2]

Mineralogical name	Epsomite
Chemical name	Magnesiumsulfate Heptahydrate
Trivial name	Bitter Salts, Reichardtite, Seelandite
Chemical formula	MgSO₄•7H₂O
Other forms	Kieserite (MgSO₄•H₂O) Sanderite (MgSO₄•2H₂O) Starkeyite (MgSO₄•4H₂O) Pentahydrite(MgSO₄•5H₂O) Hexahydrite (MgSO₄•6H₂O) Meridianite (MgSO⁴•11H₂O) Magnesium 12-Hydrate
Crystal system	orthorhombic
Crystal structure
Deliquescence humidity 20°C	90.1% (20°C), 94% (30°C)
Solubility (g/l) at 20°C	710 g/l
Density (g/cm³)	146.8 cm³/mol
Molar volume	246.48 g/mol
Molar weight	1.67 g/cm³
Transparency	transparent to translucent
Cleavage	perfect
Crystal habit
Twinning
Phase transition
Chemical behavior
Comments	can by produced from an aqueous solution under 50°C
Crystal Optics
Refractive Indices	n_x = 1.433 n_y = 1.455 n_z = 1.461
Birefringence	Δ = 0.028
Optical Orientation	biaxial negative
Pleochroism
Dispersion
Used Literature
{{{Literature}}}

<bibimport/> Authors: Hans-Jürgen Schwarz, Tim Müller, Nils Mainusch
back to Sulfate

Hygroskopicity[edit]

Fifure 2: The system MgSO₄/H₂ form -30°C to 80°C , (Diagram: Michael Steiger)

Tabelle 1:Deliqueszenzpunkte in Abhängigkeit zur Temperatur [nach [Arnold.etal:1991]**Title:** *Monitoring Wall Paintings Affected by soluble Salts*
**Author:** *Arnold, Andreas; Zehnder, Konrad*
]
10°C	20°C	25°C	30°C
86,9% r.F.	90,1% r.F.	88,3% r.F.	88,0% r.F.

Tabelle 2: Gleichgewichtsfeuchte im Salzgemisch (Mischungsverhältnis: Gesättigte Lsg. A/ gesättigte Lsg. B =1:1) [nach [Vogt.etal:1993]**Title:** *Der Einfluss hygroskopischer Salze auf die Gleichgewichtsfeuchte und Trocknung anorganischer Baustoffe*
**Author:** *Vogt, R.; Goretzki, Lothar*
]
	Ca(NO₃)₂	KNO₃
MgSO₄ xH₂O	67 (21°C)	78(21°C)

Crystallized from a water solution on a glass slide
Sampole of a salt crust of magnesium sulfate whiskers
Real sample with magnesium sulfate salts, crystallized from a water solution on a glass slide
Real sample with magnesium sulfate salts, crystallized from a water solution on a glass slide
Real sample with magnesium sulfate salts, crystallized from a water solution on a glass slide
Real sample with magnesium sulfate salts, crystallized from a water solution on a glass slide
Real sample with magnesium sulfate salts, crystallized from a water solution on a glass slide
Kieserite-crystals
Kieserite-crystals
Kieserite-crystals
Kieserite-crystals
Kieserite-crystals
Kieserite-crystals
Magnesium- ulfate, crystallized from a water solution on a glass slide
Magnesium sulfate, crystallized from a water solution on a glass slide
Magnesium sulfate, crystallized from a water solution on a glass slide
Magnesium sulfate, crystallized from a water solution on a glass slide
Magnesium sulfate, crystallized from a water solution on a glass slide
Magnesium sulfate, crystallized from a water solution on a glass slide
Magnesium sulfate, crystallized from a water solution on a glass slide
Magnesium sulfate, crystallized from a water solution on a glass slide