IRON AND MANGANESE. 
Reports on a number of the iron-ore fields of the country have been 
issued by the United States Geological Survey within the last year, 
and work in several important iron districts was carried on during 
the field season of 1902. Summaries, both of the published reports 
and of the unpublished results of the season's field work are presented 
below. A paper on the utilization of slags, prepared for the last 
volume of the report on Mineral Resources, United States, and sepa- 
rately printed, but omitted by error from the bound volume, is here 
republished. In addition to the papers included in the present sec- 
tion, the ocher deposits of Cartersville, Ga., which are closely allied 
to the iron deposits of the same region, will be found described on 
pages 427 to 432 of this bulletin. On pages 214 to 217 will be found a 
paper on the zinc-manganese-iron deposits of Franklin Furnace, New 
Jersey, which may be of interest in the present connection. A list of 
the principal previous publications by the Survey on iron and manga- 
nese ores and mining districts will be found on page 256. 
IRON ORES OF THE REDDING QUADRANGLE, CALIFORNIA. 
Bv J. S. Diller. 
Iron ore (magnetite) occurs in the Redding quadrangle at a number 
of points on the contact between diabase and the Carboniferous lime- 
stone. Numerous prospects have been opened on the contact about 
Grey Rock, northeast of Bayha and on Pit River, as well as farther 
northward, opposite the United States fishery. The openings gener- 
ally show limonite, but it is derived from the decomposition of ore in 
which magnetite and pyrrhotite play an important role, associated with 
pyrite, chalcopyrite, light-green fibrous pyroxene, and garnet result- 
ing from contact metamorphism. The prospects are generally made 
in searching for copper ore, but at one place, about a mile south- 
east of the United States fishery, on McCloud River, a much more 
promising opening is operated, furnishing the iron flux at Bully Hill. 
The ore is chiefly porous magnetite, which is often coated with irrides- 
2V.) 
