226 ‘Notes on a New Victorian Gem. 
colour, which, however, might be, perhaps, accounted for by 
their being comparatively shorter and less thick. None of 
them had any terminal planes of crystalline structure—these 
having been broken off. This stone, when of a reasonably 
pale green, is a gem-stone by no means to be despised. The 
cut specimen which lies on the table is evidence of what I 
am saying. | 
3. Transparent Red Tourmaline, or Rubellite: found in 
that district whence so many fine gem-stones have come, 
especially blue topazes, and in which it is a wonder that 
hitherto no diamonds have been discovered. _ 
The half-dozen specimens which I am able to lay before 
you to-night—all embedded in transparent quartz-crystals— 
are small, it is true, but very interesting ; for they indisput- 
ably demonstrate the presence of stone in our mines, and 
leave us but little reason to fear that where they came from 
originally, there were plenty more. 
This particular substance when transparent, I mean 
Rubellite, has a value in the scientific world far beyond its 
appreciation as anornament. It has a most rare and im- 
portant use in relation to light. Some of the very best of 
our polariscopes are formed of two thin transparent polished 
plates of it—the thinner the better, so that they are barely 
thick enough to polarize. And they possess this advantage, 
at any rate, over Nicols’ prisms of Iceland spar, that they 
do not occupy much room upon the instrument, and can be 
often used upon instruments to which it would be difficult 
to apply the prism. I used them for years and never had 
reason to be dissatisfied; and if I were going to resume 
microscopic investigation I would adopt them again. 
As a gem, it is of great beauty when its red colour is per- 
fect, the crystal free from blemishes or feathers, and of a fair 
size, say from three carats upwards, and would command a 
good price : perhaps not much less than the Balais Ruby. 
With reference to the actual determination and identifica- 
tion of these specimens of Rubellite, I have not personally 
examined them ; but, I believe, a member of the Council, 
Mr. Newberry, the scientific chemist to the Department of 
Mines, has, and has. been satisfied. From so much as I can 
judge from the angles of the crystals shown, and the striation 
well marked on the specimen in the darkest piece of quartz, 
I feel no doubt about the matter. 
Were I tempted to speculate on a matter of gem-stones, 
and the conditions under which they are sometimes found, 
