Ore of Cobalt and Maneanese. °° == 983 
eS ANotiee of « singular ore of Cobalt and Manganese ; Bip 
H. H. Haypen, Esq. of Baltimore, ¢ in a letter to the Editor. 
I have now a Circumstance to mention, which I copter’ 
of avery novel and singular nature. A few days sincea 
gentleman returning from the country into Baltimore, at the 
distance of two miles, observed some men digging for sand, 
by the road side. Among the sand thrown out of the pit he 
observed some masses that had the appearance of ore. He 
brought some of it to town, when on examination, it was 
found to contain a considerable proportion of oxid of cobalt, 
combined with Manganese. Excited by no common de- 
gree of curiosity, I yesterday, in company with Mr. : 
visited the locality of this substance. We found the pit. 
abovementioned by the road side, and which was opened 
{ believe, for the purpose of obtaining plastering sand. The 
hole or pit was sunk to the depth of aboutten feet—the sides. 
presenting to view much of the variety of stratification that 
occurs in almost every part of our alluvial region, and 1 _ 
which this pit is sunk. On examination we found the mine- 
ral above mentioned, to occur upon or between two veins or | 
strata of hard ferruginous sand, and at different heights—to 
one or the other of these it adheres. There were a number 
of masses upon the surface, at the mouth of the pit, however, 
that did not appear to have had any connection with the - 
ferruginous strata. S 
This substance occurs in masses of various sizes, and ap> 
pears to be made up of grains of sand firmly cemented to-_ 
eether by the cobalt and manganese ; so much,so as to ren- 
der its “specific gravity perceptibly greater than that of 
common substances. ‘The masses are somewhat spherical 
with surfaces inclining to the stalactitic form. The colour 
is black, inclining to a deep blue. “i 
I know of no instance in which cobalt and manganese oc- 
cur in this form and manner. It is true that Klaproth i in his 
Essays, mentions a mineral in which these two substances — 
are combined, and which is‘not described in any other work | 
that I know of. But the substance under consideration ap- 
pears to me to be an anomaly in the mineral kingdom, at 
least so far as respects its locality. Itis, as before, in a per- 
fect a alluvial bank, surrounded on all sides by strata of fine. 
