Is a rare silicate with formula (Mg,Fe2+)(Al,Fe3+)3(SiO4)(BO3)O2 and hardness of 7.
For many years has been cosidered one among 10 rarest minerals in the world, but recently a more affordable material appeared on the market. A blue-green semi-transparent crystal,also of large size has yielded stones of several carats. Flawless stoness remain rare ,especially in saturated color.
It comes from Cap Andrahomana, Anosy Region, Tuléar Province, Madagascar.
The stones has several flaws and cleavage visible planes.
Weight: 6.20 ct.