182 BULLETIN 42, UNITED STATES NATIONAL MUSEUM, 



THE JOPLIN ZINC COMPANY. 



These works are located at West Joplin, Jasper County, Missouri, 

 and treat the ores of the neighboring regions, principally the separated 

 blende from Galena, Cberokee County, Kansas. The ore is divided 

 into two grades and they are mixed in about equal proportions. A 

 portion of the wet ore as received is dried and the hot dry ore mixed 

 with wet ore, the total loss in drying being about 5 per cent. The coarse 

 ores are crushed to pass through a six-mesh wire-cloth screen. 



There are eight two-storied roasting furnaces, built in two blocks. 

 Each furnace is charged every 8 hours with 1,300 pounds of raw ore, 

 producing 1,100 pounds of roasted ore. The four Belgian furnaces con- 

 tain 112 retorts in eight rows. Each furnace is charged every 24 hours 

 with 5,100 pounds of roasted ore and 50 bushels of coke and produces 

 2,200 to 2,300 pounds of spelter. 



The collection taken by Mr. J. P. Gazzam, E. m., October, 1884, shows 

 a full series of the raw and roasted ores, the fuels, and the products. 



Ore. 



(1) No. 1 blende, separated from the ore by crushing and jigging. Value, $17 per 

 ton. (55222.) 



(2) No. 2 blende, carrying a little cbert, separated from the ore by crushing and 

 jigging. Value, $13 per ton. (55223.) 



(3) Blende, carrying a little chert ; the mixed ore ready for the roaster. (55227.) 



(4) Roasted mixed blende. (55228.) 



(5) Roasted mixed blende, ready for retorts. (55229.) 



Fuel. 



(1) Bituminous coal, used for heating the zinc retorts: from Stilson, Kansas. 

 (55224.) 



(2) Coke, used in the retorts to reduce the zmc. (55225.) 



(3) Coke, used in the retorts to reduce the zinc ; crushed ready for charging. 

 (55226.) 



Products. 



(1) Metallic zinc or spelter. (5.5235.) 



(2) Metallic zinc or spelter, showing fracture. (55230.) 



(3) Bine powder, a mixture of oxide of zinc and metallic zinc resulting from im- 

 perfect condensation. From condensers. (55231.) 



(4) Blue powder, a mixture of oxide of zinc and metallic zinc, from pulverizers. 

 (55230.) 



(5) Residue, from the retorts after the extraction of the zinc. (5.5232.) 



Accessories. 



(!) Fire clay, used for the manufacture of retorts. (55233.) 



(2) Cement, mixed fire clay and old retorts ground together, used for setting re- 

 torts. (55234.) 



(3) Ashes, used for dusting condenser mold to prevent sticking. (56278.) 



