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Transactions Texas Academy of Science. 
Kennedy, W. 
regn-ons under eonsideraitiion, and some of 'them possibly during the Ter- 
tiary, and now that the strata are exposed to erosion, the bard insoluble 
limonites resist it more successfully than tbe unconsolidated sediments in 
wbiob they occur ; tbe softer rocks are, tberefore, swept away, and tbe iron 
deposits remain upon elevated plateaus or buttes.’ ” 
Mr. Jobnson seems to bave recognized tbe existence of extensive ideposits 
of conglomerate ore. They belong to every age from tbe Eocene Tertiary 
to tbe recent. 
“Dr. Penrose appears to agree with Jobnson as to tbe age of tbe nodular 
ores being lignitic Tertiary, but tbe wbole of tbe laminated ores be places, 
and rigbtly so, in tbe glaueonitic or Claiborne Tertiary.” Peference to 
Penrose, Kept, on dron Ores, Geol. Surv. of Ark., Vol. I, for 1802, pp. 
105-106. 
“ISTumerous and careful examinations of these ore deposits throughout 
a great portion of east Texas, and particularly in Cass, Marion, Morris, 
Upshur and Harrison counties, the region in which the nodular ores are 
most extensively developed, have convinced me that these nodular ores 
do not belong to the lignitic -^tage of the Eocene, but rather that they are 
of the same age as, or probably a little newer than, or derived from, tbe 
laminated ores, which, according to Mr. G. D. Harris’s determination of 
the fauna, are of lower Claiborne age.” 
Descripbions of the Lignitic and Glauconitic divisions. 
“The general assumption of the nodular ores belonging to the lignitic 
by both Johnson and Penrose appears bo have arisen from the idea held 
by both that the regions in which these ores occur in greatest abundance 
are altogether occupied by the clays and sands of that series. While it 
is true that the deposits of the lignitic stage are extensively developed in 
Cass, Marion and Upshur, and in a more limited way in Morris and Har- 
rison counties, the marine stage is also represented, and widely spread, 
fragmentary deposits of altered greensand and glauconitic sandsbones occur 
within the limits of these counties. These fragmentary deposits often cover 
several miles of territory, and their presence is always marked by 
the occurrenee of nodular ore and a greater or less extent of laminated 
ore. This is usually in the form of very thin seams interstratified with 
the sands or occurs in a fragmentary condition scattered on the surface and 
mixed with the geodes of nodular ore. 
“In Cass county the brownish-yellow altered greensands occur in asso- 
ciation with both nodular and laminated ore at the Berry Crawford mine 
about a mile north of Atlanta, Here the section shows the nodular ore 
overlying the laminated ore and the underlying altered greensand resting 
directly upon the uppermost deposits of the lignitic series.” 
Other instances: In the neighborhood of Linden; at Cusseta. Occur- 
rence of ores in the northwestern portion of Cass and eastern portion of 
Morris counties ; in Marion and Harrison counties. 
“It must, however, be admitted that as a general rule the heavier 
deposits of nodular ore occupy positiions lying at relatively lower levels 
'than the heavy deposits of laminated ores, and it also appears to be a 
settled condition that while extensive deposits, of nodular ore overlie these 
beds, by far the most extensive and valuable of these nodular deposits 
