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Beginning at the Louisiana line with a breadth of nearly one hundred and fifty miles, stretching southwest in a gradually narrowing belt and probably fading out in Caldwell County or just beyond, there is found a series of hills of greater or less elevation which are capped with ferruginated material, varying from a sandstone with a small amount of oxide of iron in the matrix, to limonite ores of high grade. Of this division only a few of the counties of East Texas have been fully examined, but enough has been done to show the probability that the greater amount of workable ores of this belt lie east of the 96th meridian, although there may be localities west of that line at which ores of value occur. These ores are associated entirely with rocks of the Tertiary and later periods.

In the Cretaceous no iron ores of any consequence are known except in the extreme west, where deposits of ochre seem to occur in connection with strata belonging to the Fredericksburg Division of the Lower Cretaceous Series.

There are only a few ores of any value found in the Carboniferous area, and those of the Permian are not of much importance.

The Central Mineral Region, however, contains, in connection with its deposits of older rocks, large deposits of very valuable ores, including magnetite, red hematite, and various hydrated ores.

Finally, in Trans-Pecos Texas, Iron ores of the hematite and magnetic types are found in veins of considerable thickness.

Thus it will be seen that the distribution of the ores is general, extending entirely across the State from east to west.

The ores of East Texas all belong to the class of limonites, or brown hematites. They have been divided according to their physical structure, due to the manner of their formation, into three general classes:

• 1. Laminated Ores.
• 2. Geode, or Nodular, Ores.
• 3. Conglomerate Ores.

To which it may be necessary to add a fourth, Carbonate Ores.

The origin and character of these different classes of ores were discussed in the First Annual Report, and the results of our further studies will appear in this Second Annual Report. In brief these are:

LAMINATED ORES.—These ores are brown to black in color and vary in structure from a massive to a highly laminated variety in which the laminæ vary from one-sixteenth to one-quarter of an inch in thickness, frequently separated by hollow spaces, and sometimes containing thin seams of gray clay. The average thickness of the ore bed is from one