48 ids ' - On Remingtonite. 
ore. The larger contact of oxyd of iron is only so far detri- 
mental, as it impedes the action of the alkalies and oxygen to 
form a chromate, and hence, within reasonable limits, the eco- 
nomic value of a chrome ore is almost in direct proportion to the 
per-centage of oxyd of chrome. The most serious injury to the — 
value of chrome ore lies in the per-centage of sitex which con- — 
sumes a proportionally large amount of costly alkali. 
naininitisiat ee 
Art. VIII.—On Remingtonite, a new Cobalt Mineral; by 
: ames C. Boorn. 
ax : 
Remineronire occurs as _a rose-colored coating, one-hundredth 
of an inch in thickness, very soft and earthy, opake, with a pale, 
rose-colored streak. 
n a mattrass it yields water and darkens; gives with borax 
and microcosmic salt, first a feeble reaction of iron, and finally, 
when the bead cools, a deep blue color of cobalt. It dissolves in 
muriatic acid with a slight effervescence, and a nickel-green _ 
color, the latter property indicating iron associated with it; for 
pure oxyd of cobalt dissolves with a blue color, and requires but 
a small quantity of iron to change the blue to green. 'The solu- — 
tion, neutralized by ammonia, precipitated by sulphide of ammo- _ 
nium, and then treated with muriatic acid, left a large amount of 
black sulphide of cobalt ; while the muriatic solution yielded 4 
small amount of sulphide of iron. The metal is, therefore, almost 
wholly cobalt. Since a little arsenic is associated with carollite, 
this mineral was tested for arsenic, but yielded not a trace of it. 
Although the above experiments were performed on about ;;th 
of a grain, yet the mineral is clearly proved to be a hydrocarbonate 
of cobalt. The quantity was, however, much too small to de 
termine its formula, 
Remingtonite coats thin veins of serpentine, which traverse 
hornblende and epidote, and its association with serpentine, con- 
taining both magnesia and lime, reminds us of the beautiful emer* 
ald nickel, (also a hydrocarbonate) discovered by Silliman on the 
chrome ore, in the serpentine, of Lancaster county, Pa. 4 
he immediate associates of Remingtonite are serpentine, — 
hornblende, epidote, carbonate of lime, and carrollite. The copy 
per mine in which it occurs, is near F'inksburg, Carroll counts tf 
Maryland, and is under the immediate supervision of Mr. Edwar¢ 
Remington, after whom the species is named. ae 
. Philadelphia, May 15th, 1852. 
