Mineral description : Chondrodite

Chondrodite from Stakholmen, Hassela, Sweden. As small grains and crystals. Strong yellow flourescense.

Chondrodite from Innansjön, Västerbotten, Sweden. As euhedral crystals in calcite. No flourescense.

Mineral class	Silicates : Nesosilicates : Olivine group.
Chemical formula	(Mg,Fe)5(SiO4)2(F,OH)2
Crystal system	Monoclinic.
Habitus	As heavy twinned lamellar crystals, Also as massive aggregates.
Cleavage	Poor, uneven fracture.
Hardness	6-6.5
Density	3.16-3.26
Color	Yellow, red or brown. Transparent to translucent.
Streak
Luster	Vitreous.
Description	Chondrodite is a member of the humite group. The crystal structure of the humite group minerals is as layers of silicate and oxide. The silicate layer have the same structure as olivine and the oxide layer resembles brucite. In the case of chondrodite it consists of two olivine layers between each brucite layer.
Occurance	Forms in contact metamorphed limestone. Sometimes also created in carbonatites.
Associates
Notes	Soluble in hot hydrochloric acid, forming a precipitate which transform into a gelatinous mass as the solution cools down. Easily transformed into serpentine with lowered hardness as a result. Chondrodite comes from a greek word for grain. Sometimes yellow flourescens.
Locations	A not so common mineral in Sweden Mansjöberg limestone quarry, Los, Hälsingland. Commonly as yellow grains together with spinell in limestone. Åkers limestone quarry, Södermanland. As above. Hällesta, Östergötland. Gåsgruvan, Värmland. Also in sulphide mines as Kaveltorpsgruvan and Norberg field, Västmanland. Kobergs zinc mine, Värmland. Stakholmen, As crystals and massive aggregates.

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