234 REPORT OF NATIONAL MUSEUM, 1899. 



to be genetically related. In elevation they occur only at and below 

 300 feet above tide level, and most of them lie between 260 and 270 

 feet above tide. They have soft Tertiary beds both above and below 

 them at a few places, and must, therefore, be of Tertiary age. As a 

 rule, however, they have no covering, the overlying beds having been 

 removed by erosion, and are high enough above the drainage of the 

 country to be readily quarried. Erosive action has removed a part 

 of the bauxite in some cases, but there are, in all probability, many 

 places at which it has not yet been even uncovered. 



It is pisolitic in structure, and, like all bauxite, varies more or less in 

 color and in chemical composition. (Specimen No. 67600 from Pulaski 

 County.) At a few places it is so charged with iron that attempts have 

 been made to mine it for iron ore. Some of the samples from these 

 pits assay over 50 per cent of metallic iron. This ferruginous kind is 

 exceptional, however. From the dark red varieties it grades through 

 the browns and yellows to pearl gray, cream colored, and milky white, 

 the pinks, browns, and grays being the more abundant. Some of the 

 white varieties have the chemical composition of kaolin, while the red, 

 brown, and gray have but little silica and iron, and a high percentage 

 of alumina. The analyses given on page 231 show that this bauxite 

 compares favorably with that of France, Austria, and Ireland, and is 

 apparently well adapted for the manufacture of chemical products, for 

 refractory material, and for the manufacture of aluminum by the 

 Deville process. 



The Georgia and Alabama deposits have been the subject of exhaust- 

 ive study by Willard Hayes, to whose paper reference has already 

 been made. 



According to this authority the ore is found irregularly distributed 

 within a narrow belt of country extending from Adairsville, Georgia, 

 southwestward, a distance of 60 miles, to the vicinity of Jackson- 

 ville, Alabama. The only points at which it has been worked on a 

 commercial scale are at Hermitage furnace, 5 miles north of Rome, 

 Georgia, near Six Mile Station, south of Rome, and in the dike dis- 

 trict near Rock Run, Alabama. (See fig. 6.) The oldest rocks of the 

 region are of Cambrian age and are subdivided on lithologic grounds 

 into two formations, the Rome sandstone below and the Connasauga 

 shale above. The former consists of TOO to 1,000 feet of thin-bedded 

 purple, yellow, and white sandstones and sandy shales. In the south- 

 ern portion of the region the Rome sandstone is replaced by the 

 Weisner quartzite, which consists of a series of interbedded lenticular 

 masses of conglomerate, quartzite, and sandy shale. It apparently 

 represents delta deposits contemporaneous with a part or the whole 

 of the Rome sandstone. These rocks form Weisner and Indian 

 mountains, and in the latter they attain a thickness of 10,000 feet or 

 more. 



