208 Count de Bournon’s Description of 
red colour, and of a roundish form. There was lately sent to 
Mr. Greville, a parcel of imperfect corundum, found among 
the sands of the river Kirtna, in the district of Ellore,* in the 
northern part of the government of Madras. This corundum, 
some of the crystals of which were the best defined of any I 
had yet seen, was mixed with pretty large angular fragments of 
garnets, of a very deep blood-red colour, and of the most beau- 
tiful transparency. 
Zircon . The same parcel of imperfect corundum, of which I 
have just spoken, from the district of Eilore, was also mixed 
with crystals of zircon, the jargon of the lapidaries. These 
crystals, which were in perfect condition, deserve to be men- 
tioned, not only on account of their size, but also on account of 
the great number of varieties and rare forms they exhibit. Such, 
for instance, is the primitive very obtuse octaedron, which is 
in large crystals, with sides of more than six lines in length. 
I had observed this form, for the first time, fifteen years ago, 
in some crystals found in the sands of a rivulet, called Riou 
Pezzouliou, which runs between the volcanic rocks at Expailly, 
near Pay in Velay ; but these crystals were very small. The 
celebrated Rome' de Lisle, who published my account of these 
crystals, in his excellent work on the external characters of 
minerals, mentions the opinion I then entertained, and had com- 
municated to him, that the jargon and the hyacinth were only 
two differently-coloured varieties of the same substance, and 
were both derived from the same primitive form. 
The most usual colour of these crystals of zircon, is a brown, 
which sometimes inclines to yellow ; they often, however, have 
that fine j^ellowish red colour, which causes this stone to be 
* This district is contiguous to that in which the diamond mines are situated. 
