When it comes to choosing the best pick among Violet Gemstones gemstones, Purpurite is known to be a popular choice!Physical properties of Purpurite include its hardness, gravity, fracture, cleavage, etc. For any gemstone crystal, Purpurite Optical Properties are responsible for imparting various physical properties to its structure. Knowledge of these properties is equally important to gem-cutters as well as to consumers. Purpurite cleavage is nothing but the plane across which the crystal splits during cutting. Purpurite cleavage is   perfect,and specific gravity of Purpurite is 3.2-3.4.
The physical properties of Purpurite, in fact, are imparted by the chemical composition of its individual molecule. The reactivity or inertness of the crystal is solely governed by its chemical structure. Chemical composition of Purpurite is represented by MnPO 4Walter Schumann , Gemstones of the world (2001) More from other references.