THE NONMETALLIC MINERALS. 385 



concentration or treatment, as ballast, mainly to the European markets. It is 

 reported to contain 3 to 4 per cent thoria. * * * Monazite has also been found 

 in the gold and diamond placers of the provinces of Bahia (Salabro and Caravellas), 

 Minas Geraes (Diamantia), Rio de Janeiro, and Sao Paulo. It has been found in the 

 river sands of Buenos Ayres, Argentine Republic, and also in the gold placers of 

 Rio Chico, at Antioquia, in the United States of Colombia. 



In the Ural Mountains of Russia monazite is found in the Bakakui placers of the 

 Sanarka River. The placer gold mines of Siberia are reported to be rich in mona- 

 zite, which is rafted down the Lena and the Yenesei rivers to the Arctic Ocean, and 

 thence to European ports. 



Economic deposits of monazite are also reported to exist in the pegmatic dikes of 

 Southern Norway. It is picked by the miners while sorting feldspar at the mines. 

 It is not known to exist in placer deposits. The annual output is stated to be not 

 more than 1 ton, which is shipped mainly to Germany. 



Methods of extraction. The nionazite is won by washing the sand and gravel in 

 sluice boxes exactly after the manner that placer gold is worked. The sluice boxes 

 are about 8 feet long by 20 inches wide by 20 inches deep. Two men work at a box, 

 the one charging the gravel on a perforated plate fixed in the upper end of the box, 

 the other one working the contents up and down with a gravel fork or perforated 

 shovel in order to float off the lighter sands. These boxes are cleaned out at the 

 end of the day's work, the washed and concentrated monazite being collected and 

 dried. Magnetite, if present, is eliminated from the dried sand by treatment with a 

 large magnet. Many of the heavy minerals, such as zircon, menaccanite, rutile, 

 brookite, corundum, garnet, etc., can not be completely eliminated. The com- 

 mercially prepared sand, therefore, after washing thoroughly and treating with a 

 magnet, is not pure monazite. A cleaned sand containing from 65 to 70 per cent 

 monazite is considered of good quality. From 20 to 35 pounds of cleaned monazite 

 sand per hand, that is, from 40 to 70 pounds to the box, is considered a good day's 

 work. The price of labor is 75 cents per day. 



But very few regular mining operations are carried on in the region. As a rule 

 each farmer mines his own monazite deposit and sells the product to local buyers, 

 often at some country store in exchange for merchandise. 



At the present time the monazite in the stream beds has been practically exhausted, 

 with few exceptions, and the majority of the workings are in the gravel deposits of 

 the adjoining bottoms. These deposits are mined by sinking pits about 8 feet square 

 to the bed rock and raising the gravel by hand labor to a sluice box at the mouth of 

 the pit. The overlay is thrown away excepting in cases where it contains any sandy 

 or gritty material. The pits are carried forward in parallel lines, separated by nar- 

 row belts of tailing dumps, similar to the methods pursued in placer gold mining. 



At the Blanton and Lattimore mines on Hickory Creek, 2 miles northeast of 

 Shelby, Cleveland County, North Carolina, the bottom is 300 to 400 feet wide, and has 

 been partially worked for a distance of one-fourth of a mile along the creek. The 

 overlay is from 3 to 4 feet and the gravel bed from 1 to 2 feet thick. The methods of 

 mining and cleaning are much more systematic in Spartanburg County, South Caro- 

 lina, than in North Carolina regions. Although the raw material contains on an 

 average fully as much garnet, rutile, titanic iron ore, etc., as that in the North Caro- 

 lina mines, a much better finished product is obtained, and more economically, by 

 making several grades. Two boxes are used in washing the gravel, one below the 

 other. The gravel is charged on a perforated plate at the head of the upper box, and 

 the clean-up from this box is so thoroughly washed as to give a high grade sand, 

 often up to 85 per cent pure. The tailings discharge directly into the lower box, 

 where they are rewashed, giving a second grade sand. At times the material passes 

 through as many as five washing treatments in the sluice boxes. Even after these 

 grades are obtained as clear as possible by washing, the material, after being thor- 

 NAT MUS 99 25 



