204 Notes on “ Inclusions” in Gems, &e. By Isaac Lea. 
view. In some specimens these cavities exist by tens of thousands, 
and Sir David Brewster stated that in a specimen under his obser- 
vation there were about 37,000 of these cavities. I am sure that 
in one of my large cut specimens there must be more than double 
that number. It is a very common thing to see hundreds at a 
time of these cavities in the Ceylon specimens, partly filled with 
the fluids previously alluded to in these notes. But it is quite 
rare that they are found in the specimens from North Carolina. 
Still I have seen them in the transparent small fragments of deep 
blue crystals, and sometimes in the transparent light-coloured 
ones. In one specimen of the latter I discovered some most in- 
teresting cavities, which contained, beside the fluid, each a single 
cubic crystal. I had never observed an included crystal in any 
eavity in the numerous Ceylon specimens which I have examined. 
These cubic crystals have the exact form and appearance of those 
in the emerald described herein. 
In regard to the microscopic crystals in sapphire, having 
described and figured them in the papers before alluded to, I have 
little to add now. Further observation has confirmed what I then 
stated regarding the radii of Asteria. Very recently I have 
received a number of these Asteria of various colours, blue, purple, 
white, red, and dove colour ; several three-quarters of an imch in 
diameter. ‘The red and purple specimens are of peculiar beauty, 
and when examined in the sun, or any strong light, they both 
exhibit the microscopic acicular crystals with peculiar beauty, dis- 
played as they are in hexagonal form, and reflecting the spectral 
colours. The ruby Asteria is certainly among the most beautiful 
objects in nature, and the purple are very little less so. 
In some crystals of corundum there is a strong bronze reflexion, 
and this is the case with some of the large hexagonal crystals which 
were imported by Mr. 8. 8. White from India for commercial pur- 
poses, and which he distributed with so much liberality to our 
mineralogists. These bronze crystals have also been found at the 
Black Horse and Village Green localities in Delaware County, 
Pennsylvania. When examined with a good power, these bronze 
reflexions are at once seen to be caused by minute acicular crystals, 
and these may sometimes be seen in bunches. 
A pale ruby, “ Rubicelle,” which I lately received from my 
friend Hugh Nevill, Esq., Ceylon, about three carats, is a most 
interesting and beautiful gem. It has the depth and brilliancy 
almost of the diamond. It is nearly of a rose colour, and is per- 
fectly transparent. It is cut with a top table and not entirely 
symmetrical. Its refractive power is unusually great. Yet when 
this brilliant transparent gem is examined with a high power and 
strong light, the whole mass may be seen to be filled with long 
acicular crystals in three directions, parallel to the prismatic 
