806 Dr Hamiltx)n on tJie Mine of Corundum in Singraula. 
chain of quartz-rock, which I have mentioned in giving an ac- 
count of a diamond mine in the First Number of this Journal. 
We may here so far trust the report of the traders as to be- 
lieve, that the greater portion of the rocks by the way consists of 
this sandstone or quartz-rock ; although it is probable, that, in 
such an immense mass, many beds or veins of a different nature 
are contained, which naturally enough escaped the notice of the 
traders, none of them being in demand. 
Among the masses of korund brought to Merzapur, I found 
some pieces of white quartz brought by mistake ; and many of 
the masses of korund, when broken, shew that in their sub- 
stance are imbedded pieces of green talc and of micaceous iron- 
ore, besides the particles of mica that are interposed between the 
masses. Whether or not, however, the quantity of quartz, talc, 
and mica, that are intermixed, is so considerable that the masses 
should be considered as portions of an aggregate rock, it is im- 
possible to say, without visiting the place, as of course the tra^ 
ders select the masses that are most free from intermixture. 
The quantity brought to Merzapur for sale is pretty considerable, 
as this town supplies all the provinces towards the east. The 
vicinity of the quarry is inhabited by persons of the rude tribe 
called Kol, to whom the traders carry a little salt, cloth, and 
various trifles, and from whom they receive chiefly iron and 
this korund. For the latter, they seem merely to give a small 
allowance to the Kol, who help them to dig and break as much 
as will load their oxen. The Raja seems to make no claim. 
The korund from this quarry assumes a variety of appear- 
ances ; but, although I looked over great quantities, I perceiv- 
ed no crystals, nor did the traders recollect having seen any in 
that form. The generic marks of corundum seem to be great 
hardness and great specific gravity. The native artificers dis- 
tinguish that of this quarry into different kinds, as suited for 
different purposes : some serves to clean small arms, some to 
grind cutting instruments, and some to polish stones ; but I did 
not learn the marks by which the artificers distinguish the dif- 
ferent kinds ; although, it is said, that they can distinguish them 
at sight. Some of the specimens which I brought from thence, 
by my mineralogical acquaintances at Edinburgh were called 
Corundum, others Emery, and others Fibrolite ; while others 
alleged, that all these names belong in fact to one substance : 
