paratively common occurrence, being 

 often found in granitic and metamorphic 

 rocks. 



That of common occurrence is usually 

 too clouded and fractured to be of use 

 for gem cutting. There are many local- 

 ities, however, where Beryls of gem 

 quality occur. 



The finest emeralds in the world come 

 from Muso, a locality in the United 

 States of Colombia, seventy-five miles N. 

 N. W. of Bogota. It is a wild and in- 

 accessible region and the mining of the 

 gems is a precarious occupation. The 

 emeralds occur according to Bauer in a 

 dark, bituminous limestone which is 

 shown by fossils to be of Cretaceous age. 

 As emeralds in other localities occur only 

 in eruptive or metamorphic rocks, it 

 seems probable that the Muso emeralds 

 have washed in from an older formation. 

 The emerald bearing beds are horizontal, 

 overlying red sandstone and clay slate. 

 Calcite, quartz, pyrite and the rare min- 

 eral parisite are other minerals found as- 

 sociated with the emerald. The manner 

 of working these emerald mines is thus 

 described by Streeter : 



"The mine is now worked by a com- 

 pany, who pay an annual rent for it to the 

 government, and employ one hundred and 

 twenty workmen. It has the form of a 

 tunnel of about one hundred yards deep, 

 with very inclined walls. On the summit 

 of the mountains, and quite near to the 

 mouth of the mine, are large lakes, 

 whose waters are shut off by means of 

 water-gates, which can be easily shifted 

 when the laborers require water. When 

 the waters are freed they rush with great 

 rapidity down the walls of the mine, and 

 on reaching the bottom of it they are con- 

 ducted by means of an underground canal 

 through the mountain into a basin. To 

 obtain the emeralds the workmen begin 

 hy cutting steps on the inclined walls of 

 the mine, in order to make firm resting 

 places for their feet. The overseer places 

 the men at certain distances from each 

 other to cut out wide steps with the help 

 of pickaxes. The loosened stones fall by 

 their own weight to the bottom of the 

 mine. When this begins to fill, a sign is 

 given to let the waters loose, which rush 

 down with great vehemence, carrying the 

 fragments of rock with them through the 

 mountain into the basin. This operation 



is repeated until the horizontal beds are 

 exposed in which the emeralds are 

 found." 



The next most prominent locality 

 whence gem emeralds are obtained is that 

 in Siberia on the river Tokovoya, forty- 

 five miles east of Ekaterinburg. The em- 

 eralds here found are often larger than 

 any yet obtained in South America, but 

 they are not of so good quality. They oc- 

 cur in mica schist (see colored plate), 

 and often associated with the mineral 

 phenacite, chrysoberyl, rutile, etc. 



Other localities whence emeralds are 

 obtained are Upper Egypt (the source of 

 those known to the ancients), the Heu- 

 bachthal in Austria, and Alexander coun- 

 ty, North Carolina, in our own country. 

 The latter locality is no longer worked, 

 but it has aff ordeck a number of fine- crys- 

 tals. 



Aquamarines and transparent Beryls 

 are found in Siberia, India, Brazil, and 

 in many localities in the United States. 

 Dana describes an aquamarine from Bra- 

 zil which approaches in size, and also in 

 form, the head of a calf. It weighs two 

 hundred and twenty-five ounces troy, is 

 transparent and without a flaw. In the 

 Field Columbian Museum is to be seen a 

 beautiful cut aquamarine from Siberia 

 more than two inches in diameter and 

 weighing three hundred and thirty-one 

 carats. Here is also the finest specimen 

 of blue Beryl ever cut in the United 

 States. It was found in Stoneham, Me., 

 is rich sea green color in one direction 

 and sea blue in another. It weighs one 

 hundred and thirty-three carats. Numer- 

 ous other Maine localities have furnished 

 •gem Beryls. Golden Beryls are found in 

 Maine, Connecticut, North Carolina, 

 Pennsylvania and other United States lo- 

 calities, as well as in Siberia and Ceylon. 

 From them are obtained gems of rich 

 golden color resembling topaz. 



Beryl of a pale rose color is sometimes 

 found, and when of good quality is cut 

 for gem purposes, but it is of too rare 

 occurrence to be important. 



Emeralds seem to have been known and 

 prized from' the earliest times. They are 

 mentioned in the Bible in several places, 

 the earliest mention being in Exodus, 

 where they are described as one of the 

 stones making up the ephod of the high 

 priest. 



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