CORUNDUM AND ITS OCCURRENCE AND DISTRI- 
BUTION IN THE UNITED STATES. 
By Joseph Hyde Pratt. 
HISTOKICAT^ SKETCH. 
Ruby and sapphire, the corundum gems, have been known since pre- 
historic times. Our earliest accounts tell of their use among the 
ancients, both as ornaments and as money. The early Greeks and 
Romans were not only familiar with these gems, but made consider- 
able investigation into their physical properties and described their 
occurrences. 
Of the use of corundum as an abrasive, there is no record until 
recent years. Some believe, however, that the perfection of the 
engravings upon monuments of the Egyptians is due to the use of 
emery, which they might have obtained from the large deposits of the 
Grecian Archipelago. 
The first knoAvn discovery of corundimi in quantity sufficient to 
make it of value as an abrasive was that of the emery fields of the 
Grecian Archipelago, and up to 1847 all the corundum used as an 
abrasive was obtained from these islands, principally from the island 
of Naxos. In that year Dr. J. Lawrence Smith, the American pioneer 
in corundum mining, then in the employ of the Turkish Government, 
discovered important emery deposits in Turkey. The importance of 
this discovery Avas clearly realized when, in 1850, on account of the 
working of these deposits, the price of emery dropped from $140 to 
$70 and $50 a ton. Since that time both the Turkish and the Grecian 
emeries haA^e been mined and exported. 
In India, besides the occurrence of gem corundum, there have been 
Imown for many years various localities Avhere corundum not of a 
sapphire variety exists, but only in the last few years have these 
deposits been developed and the corundum mined and exported for 
abrasive purposes. 
So far as can be learned from the literature on the subject, corundum 
Avas first known in America in 1819. In that year Mr. John Dickson, 
of Columbia, S. C, sent a lot of minerals Avhich he had collected 
