FACTS ABOUT PRKCIOUS .STONKS. 
31 
would seem that in the struggle to depart from the ordi¬ 
nal'}' routine, fractures occur, which in the cud giv'e that 
delightful play of color for which opals are so famous, for 
opals are merely an amorphous form of silica combined 
with water. The fire opal from Mexico is especially beau¬ 
tiful in its caprice of colors, which range from honey-yel¬ 
low to flaming hyacinth-red. 
One of the most valued of precious stones is the eme¬ 
rald, a bright-green variety of beryl. Emeralds are full 
of flaws and cracks, so that a large and perfect specimen 
is very rare. When the stone is colorless it retains the 
name of beryl, when bluish-green it is known as aquama¬ 
rine. 
A variety of precious stone, emerald-green in color, to 
which the name “ hiddenite ” has been given, was dis¬ 
covered in rather a strange way. An emerald mine in 
North Carolina yielded but one emerald. However, dur¬ 
ing the working another kind of .stone was found, almost 
identical in color, but entirely different in composition, 
which has never before or since been found anywhere else. 
Specimens of artificially colored agate exhibited are very 
interesting. For maii}^ years the agate industry was car¬ 
ried on at Oberstein, on the banks of the Rhine. In time 
all the available material became exhausted, and to fill its 
place agate was brought from America as ballast. Some 
layers of agate, it appears, are porous and some are not. 
The stones are boiled in colors, and the porous bands take 
in the .stain while the denser ones refuse it. The result 
shows tinted bands alternating with white, as in the natu¬ 
ral .specimens. 
Tourmalines are of almost every conceivable color, and 
among them is found the interesting occurrence of a green 
outer crystal enclosing a red one. Tourmaline reminds 
one of .some of Culpepper’s herbal pre.scriptions, where a 
little of everything conies in. Indeed, it seems almost 
