136 THE 'IRON ORE DISTRICT OF EAST TEXAS. 



The geode or nodular concretionary ore occurs in the form of irregularly 

 rounded nodules or concretions of varying sizes, ranging from two to eight 

 or ten inches. Occasionally nodules of a foot or fifteen inches in their great- 

 est extension are found, but nodules of this size are rare in Harrison County. 

 In structure these nodules are usually formed of concentric rings or layers 

 lying around a central piece of brown or yellow ochreous matter, frequently 

 sand, and occasionally clay. Some are filled with a sand similar to the de- 

 posits in which the nodules are found, and others appear to have no central 

 core, as they are found hollow. This may probably be due to the absorption 

 of the central core by the inner ring, or probably due to some fracture in that 

 ring allowing the loose sand to escape prior to the addition of the succeeding 

 outer layers. From the analogous cases found in the structure of some 

 clays and the manner in which accretions or nodules are formed, it might 

 fairly be inferred that these concentrically ringed iron nodules were formed 

 in a similar manner. Among recent clays, as well as among many of the 

 clay shales belonging to the Lower Coal Measures, nodules or concentrically 

 formed concretions occur. These concretions occur in rounded, oval, and 

 other shapes and in all sizes, and appear to have been formed round a cen- 

 tral core, sometimes a piece of wood or a shell, and very frequently of a 

 harder piece of the same material as that forming the concentric layers of 

 which the nodules are made up. On the Dan Davis headright, in Harrison 

 County, many of the concretions found on the east side appear to have formed 

 around a core of ferruginous gravel and to have the central gravel firmly 

 cemented to the inner ring of the nodule. Extensive deposits of flat or 

 slightly raised ore on the north side of the Peter Pinchum headright show 

 the same tendency of the ore to concentrate upon and attach itself firmly to 

 the underlying gravel. 



In Harrison County nodular ore occurs chiefly scattered over the north 

 side of the Clery Grillet headright and among the series of small rounded 

 yellow sand hills in that neighborhood. It is also found in scattered quanti- 

 ties along the sides of the Hynson Mountain and on the hill to the west. On 

 the southwest corner of the W. C. Crawford headright, about two miles west 

 of Hallville, the summit of the ridge forming the termination of the central 

 plateau in that region is covered with a broken mass of red sand and nodular 

 ore to a depth of about five feet. A short distance north of this, at" 'Squire 

 Lynch's place, where the Marshall and Longview road crosses the same ridge, 

 the nodular ore is found in thin scattering quantities. 



The west end of the Dan Davis headright is occupied by deposits of a 

 laminated ore lying close to the surface. The nature of the district changes 

 near the center of the headright at Mr. Black's house, and from that point 

 eastward through the Davis and partly across the Bailey Lout headright the 



