322 Dr. Davy on the Geology and Mineralogy of Ceylon . 
5. Ceylon is celebrated for spinell, sapphire, and corundum. 
They occur here, I believe, in gneiss. Spinell is comparatively rare ; 
I have got a few small and beautiful crystals of it, which were said 
to have been found in the Kandian country $ and I have detected 
it in specimens of clay iron ore from a part of the interior, where 
gneiss is the only rock. 
Sapphire is much more common ; it occurs in the gneiss alluvion 
of Matura and SafFragam, and in the neighbourhood of Arisa- 
haville and Ruanwelle. Hitherto I have searched in vain for it in 
the rocks surrounding the places in which it is found. All the va- 
rieties of sapphire occur in perfection in this island, as the blue, red, 
yellow, green, white and star stone ; and in the places already men- 
tioned. The green sapphire is very rare ; the only specimen that 
I have seen of it appeared to owe its colour to the blending of blue 
and yellow. 
Corundum is less frequently met with than the sapphire. I 
know of one place only where it abounds in the island ; it is a spot 
called Battagamunna, near Atala in the province of Uwa. It is 
collected and brought to Kandy as an article of revenue ; the 
specimens of it I have examined are either irregular masses, or 
crystallized in the form of low six-sided prisms. I have not yet 
been into Uwa ; but from the specimens of rocks that I have 
procured from that quarter, and from all the information I can 
collect, I have little or no doubt that the matrix of this mineral is 
gneiss, on a granite rock. 
I may observe that Ceylon affords specimens indicating a grada- 
tion between sapphire and corundum. The chrysoberyl is said on 
good authority to occur in the sand of rivers in this island : I have 
no doubt of the fact, but hitherto I have not met with the mineral. 
6. Of the felspar family, I think it likely several species may 
