J. Lawrence Smith on E mery. 359 
2d. The limestone immediately in contact with the emery 
differs almost invariably in color and composition from the mass 
of the rock; and.at Kwdah, where the marble forming the rock 
is remarkably pure:-(as evinced by analysis), the part in contact 
and contains a large portion of alumina and oxyd of. iron. 
thickness of this interposing coat between the emery and the 
marble is variable ; but what is certain, it passes gradually into 
white marble, so that their crystalline structures run into eac 
other, showing that they are one and the same rock. Had the 
Masses of emery been broken from an older rock and imbedded in 
_the marble at ‘its:formation, there is no reason why the contact 
‘Should not always be direct and immediate without this transition 
from ferro-aluminous limestone to pure marble. What we see is 
_ just what should be expected in ferruginous and aluminons min- 
_ erals forming and separating themselves from a limestone not yet 
- consolidated 
ed for exploring this mineral. It has been stated that at all 
the localities under consideration, but principally at Gumuch and 
axos, the emery exists in great abundance detached from the 
rock in a red earth; now this earth is simply the result of the 
decomposition of this heterogeneous calcareous envelope, which 
from its nature is easy of disaggregation by the influence of at- 
mospheric agents. Had the emery been in immediate contact 
with the marble we could -hardly have expectéd this spontaneous 
“Separation in so great a quantity. 
I have in some iristances seen small nodules of emery in small 
cavities in the-rock but perfectly detached. : 
e-immensé mass- alluded to as covering several square 
yards of surface is another evidence of the emery. having been 
formed in the limestone ; for this mass does not consist of a single 
piece, but of a number of different sizes, not lying together 
_ irregularly, but with their contiguous surfaces more or less paral- 
lel, although removed a little distance from each other; in fact, it 
1s just what we would expect in a large mass that for some cause 
or other had been fissured in various directions. 
4th. Yet another circumstance to be remarked in connection 
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value of this argument is better understood on examining the 
Specimens in my possession 
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with the emery is of a dark yellow-color resembling ‘spathic iron, 
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; ot TD hts kind of separation between the emery and the marble 
has been highly useful in the facility that it has indirectly afford- 
