174 
MANGANESE DEPOSITS OP INDIA : MINERALOGY. [PaRT I 
observed on garnets. I have not yet found any on Indian garnets.^ 
Some crystals of a manganese-garnet of dark orange-brown to dark 
brown colour, up to | inch in diameter, and set in a matrix of quartz, 
were obtained by Mr. C. E. Low from near Kudsuri in the Balaghat 
district. Some of these crystals show a combination of the trapezohedron 
and dodecahedron, the two forms being about equally developed, whilst 
some show trapezohedral faces only. The garnet reacts for manganese, 
but it is not yet known if the mineral is to be referred to spessartife. 
From what has been written above it will be seen that the common- 
est, and in fact the characteristic, form of this mineral is the trapezohedron, 
n, or (211) ; whilst faces of the rhomb-dodecahedron, d, or (110), and of 
the hexoctahedron, s, or (321), are not uncommonly found. I have 
seen no twinned crystals of Indian manganese-garnets. 
One trapezohedral crystal obtained from Waregaon shows that a 
few of its faces are really made up of vicinal hexoctahedral faces, one 
trapezohedral face being composed of two very flat hexoctahedral faces, 
as in figure 19. 
The crystals are usually about equally developed along all three axes ; 
but occasionally they are distorted. Thus the dodecahedral crystals of 
Jothvad (see page 170) tend to be prismatic. A crystal from Waregaon 
is very flat owing to being much more developed along two of the axes 
than the third. This crystal, also, indicates that the trapezohedral faces 
are composed of vicinal hexoctahedral ones. 
In one case I have noticed under the microscope what seems to be 
well marked cleavage, evidently parallel to the faces 
" ' of the rhomb-dodecahedron, d ; for these cleavages 
made angles of 60° with each other. The specimen in which this pheno- 
menon was noticed was a piece of gondite fi'om the Kajlidongri 
mine, Jhabua State. The fracture ol spessartite is very variable. Some- 
times it is sub-conchoidal, especially on unaltered examples. At other 
times it is irregular or uneven. 
1 In one specimen — a piece of rock fiom C'hargaon showing trapezohepdral 
crystals of spessartite set in a matrix of rhodonite, barytes, apd a green phosphate 
I thought I had found an embedded octahedron of spessartite, with one corner, 
showing four faces, piojecting, Hence the insertion of fig. 20. Liiter, feelirg 
doubtful, I broke up the specimen and found the supposed octahedron to be a 
trapezohedron, with the top co'ner (as oriented in lig. 13) piojecting. 
