Barite and fluorite France

Barite and fluorite from the quarry of Saint Peray in Ardèche (France) (year 2008).

Chemical composition: barium sulfate (BaSO₄)

Crystal form: automorphic and lamellar.

Hardness: 3 - 3.5

Color: white 

Streak : white

(In mineralogy, the line is the colour of the powder of a mineral, obtained by rubbing the mineral on an unglazed porcelain plate. This method is used to identify minerals, as the colour of the streak is often more constant than the colour of the mineral itself, which can vary due to impurities, oxidation or other factors).