abstracts: mineral resources 325 



MINERAL RESOURCES.— .4 renew of the phosphate fields of Florida. 

 W. H. Waggaman. Bulletin 76, Bureau of Soils. 

 The author describes the classes of Florida phosphate which are at 

 present commercially important. These are the hard rock phosphate 

 occurring along the west coast of the Florida peninsula and the land 

 pebble phosphate which is mined to the south of the hard rock fields in 

 Polk and Hillsboro Counties. The geological occurrence physical 

 properties and their relation to the chemical composition of the rock are 

 described, the methods of mining and preparing the rock for the market 

 are described, and the cost of production and percentage of waste mate- 

 rial are estimated. Possible means of utilizing this waste are suggested. 

 The present output and conditions in these fields and the future outlook 

 of the industry are discussed. W. H. W. 



MINERAL RESOURCES. — A report on the natural phosphates of Ten- 

 nessee, Kentucky and Arkansas. W. H. Waggaman. Bulletin 81, 

 Bureau of Soils. 



The geological occurrence, physical properties and chemical composi- 

 tion of the different varieties of rock in the phosphate fields of Tennessee, 

 Arkansas and Kentucky, are described together with the methods of 

 mining and treating the material for the market. In Tennessee there 

 are three types of phosphate which are commercially important, namely 

 the brown rock of ordovicean age, the blue rock or devonian phosphate, 

 and the white rock which has been laid down at a later period. 



The former wasteful methods of mining in these fields are being rapidly 

 supplanted by more modern and economical methods. Many of the 

 old dumps and waste heaps are being worked over and valuable phos- 

 phate rock thus recovered. The cost of preparing the brown and blue 

 rock for the market is approximately $2.50 per ton. The white rock is 

 not being mined at present. 



The deposits of phosphate in northern Arkansas are not generally 

 regarded as of much economic importance but they are being worked to 

 a considerable extent and are well situated to supply the demand for 

 fertilizers west of the Mississippi. The rock is mined like the blue rock 

 of Tennessee and belongs to the same Geologic period. The grade of 

 the rock is lower but the average cost of mining it is probably not as 

 great. 



The phosphate deposits of Kentucky have not as yet been exploited. 

 They occur in the blue grass regions near Lexington and are probably 



