1090 
MANGANESE DEPOSITS OF INDIA : DESCRIPTIVE. [ PaRT IV : 
and other places, some of the silica removed irom the felspar and 
manganese- garnet when they suffered alteration to kaolin and manga- 
nese-ore respectively. Some chert is also^associated with the vein quartz 
and seems to have then resulted from the solution and re-deposition of 
the latter during its replacement by manganese-ore, as described above. 
The most common form of manganese-ore at Garbham is psilomelane, 
of which almost every variety may be found, 
thfore^ '"'^ °' ^^^^ stalactitic, mammillated, botryoidal, and 
kidney-shaped masses, to irregular cavernous 
ore, compact dull-grey ore, and the light shining lead-like variety found 
also at Avagudem (which see for analysis). A complete analysis of a 
picked specimen of dull grey-ore (? a variety of psilomelane) with a 
few white specks (? kaohn) and numerous tiny octahedra (? mangan- 
magnetite) was made by Messrs. J. & H. S. Pattinson with the following 
result : — 
Specimen No. A. 228. 
MUO2 65-73 
MnO 2-66 
FeA 17-29 
AljOg 265 
BaO 0-16 
CaO 0-49 
MgO 0-16 
K.,0 1-62 
Na.O 0-32 
Sid, (combined) 2-60 
SiO."(free) 0-40 
Sulphur 0-014 
p„0. . - 0-698 
As.,6- 0047 
CoO ' 0-15 
NiO Nil 
CuO . . . 0-005 
PbO Nil 
ZnO Nil 
TiO. 0-03 
Clilorine and fluorine ...... Nil 
H„0 (combined) 4-40 
Moisture at lOO'^C 0-70 
CO., Nil 
10'0-154 
This is equivalent to : — 
Maneanese ........ 43'61 
Iron 12-10 
Silica (total) 3-00 
Phosphorus ....... 0305 
