known by the Name of Turquoise. oe 
‘opake gems ; others, on account of their blue or green co- 
lour, have ranged them among the ores of copper. 
« The turquoises,” says M. Chaptal*, ‘* are merely 
bones coloured by the oxides of copper. The colour of the 
turquoise often passes to green, which depends on the al- 
teration of the metallic oxide: the turquoise of Lower Lan- 
guedoc gives out a/fetid smell on the action of fire, and is 
decomposed by the acids; the turquoise of Persia gives out 
no smell, and is not attacked by the acids. Sage supposes 
that in the latter the osseous part is agatised.” 
Plenty of turquoises are found in Persia, and none in 
Turkey, as the name would incline us to believe: they are 
dug out of two mines}; the one is called the Old Rock, 
three days’ journey from Meched, to the north-east, near 
Nichabourg; the other is five days’ journey from Meched, 
and is called the New Rock. The turquoises of the latter 
mine are of a bad blue inclining to white; and they are sold 
at a very low price. Since the end of last century, however, 
the king of Persia has prohibited all digging at the Old Rock 
except on his own account ; because the Persian goldsmiths 
work only with the file, and do not understand the art of 
enamelling upon gold, and therefore they make use of the 
turquoises of this mine for decorating sabres, ponjards, 
and other pieces of workmanship, in place of enamelling 
them. They shape the turquoises into flowers and other 
figures, and then insert them into enchasements. 
I shall add some other details extracted from different 
works, and for which T am indebted to the politeness of 
M. Haiiy, the celebrated mineralogist. 
Turkis (Turquoise), Reuss, p. 511, part ie vol. aii. *“'The 
turquoise has been always regarded as the tooth of an un- 
known animal, the sky-blue colour of which arises from 
the oxide of copper, and according to some from the oxide 
of iron: this has caused it to be classed in the calcareous 
as well as in the coppery order of bodies, as an animal pe- 
trifaction (odontalite). 
Lommer, in the ‘* Alhandlungen einer privat geschell- 
* Elements of Chemistry. 
+ See l’Abrégé des Voyages, par M. de la Harpe, tom. vi. p. 507. 
schaft 
