Bischofite

Bischofite
Bischofite from Antofagasta, Chile
General
CategoryHalide mineral
FormulaMgCl2·6H2O
IMA symbolBsf
Strunz classification3.BB.15
Dana classification09.02.09.01
Crystal systemMonoclinic
Crystal classPrismatic (2/m)
(same H-M symbol)
Space groupC2/m
Identification
ColorColorless to white
Crystal habitFibrous to massive
Twinningpolysynthetic
CleavageNone
FractureConchoidal to uneven
Mohs scale hardness1.5–2
LusterVitreous – greasy
StreakWhite
DiaphaneityTranslucent to transparent
Specific gravity1.56
Optical propertiesBiaxial (+)
Refractive indexnα = 1.495
nβ = 1.507
nγ = 1.528
SolubilityDeliquescent
References

Bischofite is a hydrous magnesium chloride mineral with formula MgCl2·6H2O. It belongs to halides and is a sea salt concentrate. It contains many macro- and micro-elements vital for human health, in much higher concentrations than can be found in sea or ocean salt. The main bischofite compound is magnesium chloride (up to 350 g/L), moreover, it contains about 70 other elements as impurities, including potassium, sodium, bromine, boron, calcium, silicon, molybdenum, silver, zinc, iron and copper.