456 G. W. Hawes on Diabantite in amygdaloidal Trap. 
This sneivein does not differ essentially from the preceding, 
and gives an oxygen ratio still nearer to 4:2:6:3. This ratio 
may therefore be taken as the correct one, “sina it a uni- 
silicate of the pyrosclerite group with the formula : 
+ 4H1)‘Si? + 3H. 
Although agreeing with pyrosclerite in oxygen ratio, the much 
greater proportion of iron appears to authorize its recognition 
as a distinct species. 
Dr. K. L. Th. Liebe, in his article on the diabase of the Voigt- 
land and Frankenwald,* gives analyses of a chlorite of like 
occurrence which lie carefully selected from specimens panes 
at several different points, and which he name anta- 
chronnyn. Although his analyses differ somewhat sea — 
ere given, it is evident that the material he worked upon 
very similar to the above, and like it in mode of occurrence 
and probably the same species. But since his long name, 
“‘diabantachronnyn,” which was intended, as he says, to ex- 
press the idea that the mineral is the coloring ingredient of the 
diabase, does not convey that meaning, the Greek of the latter 
part of the word not signifying color, and since the name is not 
in accordance with the principles of mineralogical nomenclature, 
I have taken the liberty of shortening it to diabantite, which 
though not expressing all pe Liebe intended to convey, still 
indicates its relation to dia 
Chlorites approaching ig species in composition have been 
often analyzed with varying results oe have received various 
names ; but the great ease with w decomposition takes 
place upon such material under artes action makes it easy to 
derive from ita great number of intermediate products. The 
seams and cracks of both the diabase and dolerite of this 
region are often filled with a soft ferruginous chlorite, but 
which contains varying amounts of sesquioxide of iron, and is 
not homogeneous. A chlorite of the kind analyzed could 
hardly be expected to withstand the influence of percolating 
waters. 
The amygdaloidal cavities afford additional evidence to that 
already given, proving that the hydration of these rocks was 
produced by vapors that gained access to the molten mass dur- 
ing its ascent to the surface. these cavities often contain 
bitumen, which in all probability’ was derived from the bitumi- 
nous shales of the region, and was carried up along with the 
other products received from the strata and the subterranean 
streams encountered, aud deposited in the cavities. This 
bitumen is widely distributed in the amygdaloidal trap, as was 
* Jahrbuch fiir Mineralogie, 1870, p. 1. 
t+ Kenngott has endeavored to prove that Liebe’s mineral was common ripido- 
lite; but these analyses show that it has a very di ratio. 
