Chap. XL. ] vizagapatam : kotakarra. 
1097 
There is a considerable quantity of detrital ore resting on that in situ. 
These workings consist of a number of shallow excavations, not more 
^ than 20 feet deep, made by the Vizianagram 
Mining Co., and lie about 200 yards north of 
the village at the east base of a small liill of quartzites containing little 
black specks of an iron-ore altering to hematite. The dip of the quartz- 
ite is pretty steep to E. 10° S. and the hill strikes S. 10° W. 
In one pit there is a very interesting exposure. The strike of the 
^ i j , J ., rocks is E. 25° S. with a fairly steep dip to the 
Opalized kodunte or apii- •' r i 
t'.te-spandite-felspar-rock. south side, curling over to vertical. The follow- 
ing rocks are exposed in order from N. to S, ; — 
(1) dirty psilomelane banded with chert, and both containing abundant 
scattered manganpse-garnets ; 
(2) banded rock of spandite and greenish blue apatite in a white siliceous 
matrix (probably opal). This rock was probably once apatite -spandite- 
orthoclase-rock (kodurite), of which the felspar has subsequently been 
replaced by opaline silica (see pages 256—261); 
(3) psilomelane in layers 1 to 2 inches thick ; 
(4) kaolinized quartz-felspar-rock with some green clay ; 
(5) kaoHnized quartz-felspar.rock with clayey and limonitic bands ; 
(6) soft manganese-ore with limonite and abundant residual patches of 
manganese-garnet. 
I neglected to measure the thicknesses of the above rocks, but the 
total was probably not more than 5 feet. Eock 2 is, owing to the 
siliceous cement, quite hard and not friable and powders like the 
customary examples of apatite-spandite-felspar-rock, in which the felspar 
is kaolinized, seen elsewhere in this district. It is intruded by a coarst3 
pegmatite of quartz and felspar. Overlying this exposure is a mixture 
of chert, altered pegmatite, and psilomelane with pyrolusite, all 
together forming a fairly soHd rock, which was formed, possibly, by the 
chemical alteration of the underlying rocks. 
In another pit I found a loose rounded block of fine-grained 
pyroxene (?diopside)-scapolite-quartz-rock con- 
quarte-rock.'^*^°^'*^' taining also sphene, apatite, and occasional 
plagioclase. It is probably a variety of the 
scapolitic or calcareous gneisses. 
At the time of my visit work was said to have ceased for three years 
at this locality, previous to which a few thousand tons of second-grade 
