238 CONTRIBUTIONS TO ECONOMIC GEOLOGY, 1902. [bull. 213. 
strongly developed schistose structure. The ore passes into the 
quartzite by a gradual transition, and only the richest parts of the 
bed can be worked. The greater part of it is quite siliceous. Even 
the purer portions of the ore contain many inclusions of white sac- 
charoidal quartz, generally drawn out into long, slender filaments. In 
some cases the iron appears as flattened oolitic grains embedded in a, 
ground mass of white quartzite. It is evident that in these deposits 
the iron existed in the quartzite before the alteration of the latter. 
It may have been in the form of the carbonate or of the hydrous 
oxide, and possibly, in £>art at least, of the sulphide. Some portions 
of the ore contain what may possibly be greatly altered pseudomorphs 
after pyrite. The ore is not appreciably magnetic; is nearly black in 
color and has a bright metallic luster. It is called "gray ore" by the 
miners, to distinguish it from the brown hematites of the district. 
The specular hematite outcrops at short intervals, along a line 
lying a short distance east of the Western and Atlantic Railroad, from 
a point about 1 mile north of Emerson station to the north side of the 
Etowah River. It is possible that this belt extends still farther north, 
so as to include the workings noted near Warford, but outcrops 
have not been noted in the intervening space. South of the Etowah 
River the specular hematite has been worked to some extent, by 
means of pits, open cuts, and a short tunnel, on the properties of the 
Roan and Etowah Iron companies. The ore from these properties 
ranges from 55 to G5 per cent in metallic iron, and at several of the 
pits it falls within the Bessemer limit for phosphorus. The ore 
bodies, however, do not appear to be sufficient in size to justify 
exploitation on a large scale. In many of the pits the silica content 
is high, and no cheap and simple concentrating system is available 
for separating the purer ores from the more siliceous portions. 
Broivn hematiti or limonite. — Several varieties of this ore occur in 
the southern Appalachians, and are more or less distinct in their 
appearance, manner of occurrence, and mode of formation. The 
most important of these are (1) gossan ores, (2) Tertiary gravel ores, 
(3) concentration deposits, and (4-) fault deposits. Only the two 
latter varieties occur in the Cartersville district; but all four of 
the classes occur in the immediate vicinity, and may be briefly 
characterized. 
1. The best-known deposits of gossan ore occur in the Ducktown 
district. As is well known, copper occurs there associated with great 
quantities of pyrrhotite. The latter has been oxidized at the surface 
to limonite, and during the process of oxidation the copper has been 
concentrated at the bottom of the weathered zone, forming the rich 
deposit of "black copper" overlying the unaltered pyrrhotite. The 
gossan ore has a variable depth, down to 50 feet or more, and con- 
sists of soft, porous, ocher-yellow limonite. 
2. During Tertiary time the valley region was reduced very nearly 
