SYNOPSIS OF PART 1. IxiX 
p. 76, (1906). It is to be regarded as the crystalline form of 
psilomelaiie, and is a crystalline manganate of the general formula 
mR"2MnO-, + «R"'4(Mn05)3, in which R" may be Mn, Fe, Ba, Ca, Mg, 
K2, Na2, Co, Ni, Cu, and H2, and R'"may be Mn, Fe, and Al. The 
most important of the elements replacing the R" are usually Mn, 
Ba, K2, and H2, named in order of importance, and of those replacing 
R'", Fe and Mn. An analogous mineral is the one found in Arizona 
and named coronadite. It is chiefly a lead-manganese manganate, and 
is probably isomorphous with hcllandite. The crystallography of 
hollandite has not yet been properly worked out, although definite 
crystals are available. The crystals are found at KajHdongri in Central 
India ; but the mineral has also been found at Sitapar, Balaghat, 
Jnnawani, and other localities in the Central Provinces, and is largely 
exported from two of the mines, namely Sitapar and Balaghat. It 
varies in colour from light grey to almost black, has a hardness of 6 on 
crystal faces and of 4 on fracture surface. The specific gravity of the 
mineral from the type locality, Kajlidongri, is about 4"95, whilst the 
value for that from Sitapar is only 4"70. 
Psihinelane. — This is the most widely spread and abundant ore 
of manganese found in India. Several analyses are given and it is 
shown that the supposition first put forward by Laspeyres that 
psilomelane may be regarded as derived from a hypothetical acid 
of the composition H4Mn05 is in all probabihty correct. The general 
formula is the same as that already given for hollandite, and the 
relative importance of the constituents replacing R" and R'" is about 
the same. An example is given of the way in which an analysis of 
a piece of ore composed mainly of a mixture of psilomelane and 
braunite can be recalculated into terms of the mineralogical composi- 
tion of the ore. 
Beldongrite. — This is the name given to a black pitch-like 
mineral that is probably to be regarded as the product of alteration 
of spessartite. After eUminating other substances from the one 
analysis made, the balance is found to correspond very closely to the 
formula GMn30.n.Fe203.8H20. If this be the true composition 
of the mineral, then there is no doubt that it is a distinct mineral, to 
be regarded as closely allied to psilomelane, but with ferric oxide and 
water in addition to the MnsOr,, which can be regarded as Mn2Mn05; 
