ST. JOHN DEL REY

Evening Post, Volume CVI, Issue 126, 24 November 1923, Page 16

ST. JOHN DEL REV

DEEPEST MINE IN THE WORLD.

The St. John del Key mine in Brazil is the deepest mine in the world, reports Thomas T." Read, supervising .engineer of the United States Bureau of Mines, in the "New York Time 3." "Amongi thef large number of deep ■'mines in the ■ world, there are several which do not differ much in depth," he says. "The St. John del Rey mine has reached a vertical depth' of 6726 feet below the top of its shaft; miners enter it, however, through an adit which intersects the shaft 324 feet below the surface. ■ •

'In the Kolar gold field of India there are a number of deep shafts, <><», of which reaches to a vertical depth of 6140 feet below surface. ' In South Africa the Village Deep reached 6100 feet early in 1921. The. City Deep, Ltd., is expected to sink to a depth of ii r. ' °ufc Pre3umably the St. John del Eey will be deeper than that, since it has been going lower at the rate of 150 feet a year. "The deepest shaft in the United states, the Hamarack No. 5, although it is only 5308 feet deep, actually approaches nearer to the centre of the earth (4100 feet below sea level, a« against 3958 feet at St. John del Key). The deepest workings in the Calumet and Hecla go down to 4600 feet below sea level.

"The St. John del Bey is worked by the oldest registered English mining company, which was organised in 1830, to work a mine at a considerable distance from this one. That mine proved unprofitable, and in 1837 operations were transferred to the St. John del Eey deposit, where operations have been practically continuous ever since. Both the composition of the ore, consisting of quartz, carbonate of iron, and magnesia and sulphides, with which the gold is apparently associated, and the method of working the mine are unusual. "It is worked," says Mr. Read, "through a series of five shafts,, of which only the first reaches the surface. - The • others merely connect the levels, and sstrictly should bo called winzes. Tho shafts are all in the wall rock on tli3 north sido of the ore body aud are connectad witu it hv crosscuts '