MARION COUNTY. 105 



glossy and black on the inside. They are generally hollow, though they 

 sometimes contain masses of the same mottled clay as that separating the 

 different beds of ore. The clays and sands separating the beds often con- 

 tain loose geodes. 



About a mile northwest of this locality, and on the same plateau, the follow- 

 ing section was seen in a pit:* 



1. Sandy clay soil, dark brown, with ore pebbles and geodes composing 



two- thirds of the stratum 12 to 15 inches. 



2. Brown laminated ore, with some concretions 6 inches. 



3. Ferruginous sand, with concretions and hardpan 18 inches. 



4. Ore in thin seams 4 inches. 



5. Mottled clays, with thin iron scams and geodes 4 feet. 



These strata dip at from fifteen to twenty-five degrees northeast. 

 The following is an analysis by J. H. Herndon of ore from this field: 



Ferric oxide *64.42 percent 



Silica 26.435 per cent. 



Alumina 3.816 per cent. 



Lime . 284 per cent. 



Magnesia 1.014 per cent. 



Sulphuric acid . . . . f 1 . 838 per cent. 



Phosphoric acid, per cent. 



Water per cent. 



Oxide of manganese 1 . 895 per cent. 



Total 99.702 



♦Metallic iron, 45.09 per cent. fSulphur, 0.7352 per cent. 



In addition to these three ore fields, there are smaller areas containing a 

 considerable supply of ore of the laminated, nodular, and conglomerate char- 

 acters. The most important of these is a deposit of nodular and laminated 

 buff crumbly ore lying along the line of the Texas and Pacific Railway, about 

 three miles north of the town of Jefferson, on the M. K. Hammond, A. Rich- 

 ardson, and Joseph Watkins headrights, comprising an area of about two 

 square miles. 



The general division of the ore in this field is that of nodular concretionary 

 ore, occupying an area of probably seventy-five or one hundred acres, and 

 having an average thickness of about from eighteen inches to two feet. This 

 ore lies in a brownish orange-colored sand, and is mixed in some places with 

 a conglomerate of transparent quartz crystals imbedded in a brown iron 

 matrix. These crystals do not exceed one-half inch in their greatest diame- 

 ter, and the conglomerate is broken into small pieces, ranging from two to 

 four inches in diameter. 



The following analysis by J. H. Herndon is from a specimen of ore from this 

 field: 



* First Report of Progress, p. 57. 



