It possesses double refraction in a very nigh degree.
Its cleavage resembles that of the diamond.
the jargoon of Ceylon, there is the inferior or Western stone, which is
found in the Trapp rock, near Lisbon ; in the masses of sienite in the
county of Galway ; at Expailly in France ; at Leonedo in the province
of Vicenza, and in the auriferous sands of the shifting district of
jargoons of a large size are seldom found, those in commerce acquire a
certain price, although never extravagantly high. A very fine pure
olive jargoon, of -012 mètres square, is worth 100 lire ; one less
pure, of another colour yet of equal size, costs 25 lire.