CHRYSOBERYL TOPAZ. 35 
of seals and precious stones European workmen con- 
sider it preferable to emery ; but, for minute engraving, 
it is much inferior to diamond powder. 
60. CHRYSOBERYL is a gem of yellowish or brozcnish 
green colour, harder than quartz (76), and sometimes trans- 
parent ; but often only semi-transparent, in which case it exhi- 
bits a bluish light, flout ing in the interior of the stone. 
It is usually found in rounded pieces,, but is sometimes crys- 
tallized in compressed six-sided prisms, and in double six-sided 
pyramids. 
So little is this gem in request in Europe, that it is 
seldom to be found in the possession of jewellers ; but 
in Brazil it is considered inferior only to the diamond. 
It is usually procured from South America ; yet it oc- 
curs in Saxony ; and, with the ruby and sapphire, 
amongst sand in the rivers of Ceylon. 
Such is the hardness of the chrysoberyl, that, when 
properly polished, which is a difficult operation, it is 
capable of receiving a lustre nearly equal to that of the 
diamond. We are informed that, a few years ago, a 
considerable number of these gems were imported into 
this country from Brazil, but that the greater part of 
them were entirely spoiled by inferior workmen, and 
that the rest were so ill-cut that they remained unno- 
ticed, and without value. The smaller stones are said 
to appear to most advantage in circular ear-drops ; and 
the larger specimens form necklaces and ring stones of 
great beauty. 
The variety which exhibits an opalescent appearance, 
or presents a bluish light, undulating as it were in the 
interior of the stone, and changing its situation ac- 
cording to the position of the observer, is chiefly valu- 
able as an article of curiosity : the transparent kind is 
always preferred by the jeweller. 
SCHORL FAMILY. 
61. The TOPAZ is a ge?n usually of a wine-yellow colour, 
but sometimes orange, pink, blue, and even colourless, like rock 
