108 ; [JunE, 
June 29th. 
Vice-President Brincrs in the Chair. 
The Committee on Dr. Owen’s paper on a new Mineral from Califor- 
nia, reported in favor of publication : 
Notice of a New Mineral from California. 
By D. D. Owen, M.D. 
Mr. Henry Pratten, one of my assistants in the geological surveys in the 
North West in 1848 and 1849, went to California in the spring of 1850, and 
returned last February. Being interested in mineralogy and geology, he made 
observations in these departments of science, both on his way out and during the 
time he remained there. 
The mineral in question he obtained at a locality known as the Wisconsin 
and Illinois claim, near Nevada City, at which place he resided most of the 
time he remained in California. 
At the time he collected this mineral it struck him as something remarkable 
and different from anything he had previously observed; and he made at the 
time some experiments on its blowpipe reactions, without being able positively 
to decide what it might be. 
He then first submitted it to a distinguished mineralogist, who referred it to 
the species Karpholite. 
In comparing its blowpipe reactions with that mineral, Mr. Pratten doubted 
the correctness of the apacliaon that it belonged to the species Karpholite, and 
so did Dr. Norwood, who also examined its blowpipe reactions ; and they came 
to the conclusion that its indications before the blowpipe resembled more those 
of Molybdic acid. 
When I returned home last March, Mr. Pratten submitted it to me and I made 
a qualitative examination of the mineral in the humid way, and ascertained, 
from the reactions of the solution of the mineral with sulphuretted hydrogen, 
lodide of potassium, and ferro-cyanide of potassium, that the principal consti- 
tuents were molybdenum and iron. 
I found, moreover, that it was easily acted on by liquid ammonia, the molyb- 
denum being dissolved, while oxide of iron was set free in brownish red flocks. 
These chemical reactions proved that though the mineral resembles Karpho- 
lite in the yellow color of its fibrous, acicular, tufted crystals, it is quite 
different in its chemical constitution. 
I made, also, an approximate quantitative analysis on a centigramme of the 
mineral, which was all that could be spared at that time, by solution in liquid 
ammonia; collecting the precipitated iron on a filter, washing and weighing it 
after ignition. The molybdenum was then separated by sulphuretted hydrogen. 
The solution freed from molybdenum was evaporated with addition of hydro- 
chloric acid to free the solution of HS; after filtration it was evaporated to 
dryness and ignited, and the small percentage of alkali and magnesia weighed 
together; the magnesia, after being separated by peroxide of mercury, was 
weighed by itself. 
The result of the analysis gave : 
H—Water . . ’ : elo 
Mo (?) Molybdie acid (?) : » 40 compound of molybdenum and oxygen 
Fe Peroxide of iron . A 2.00 
Alkali Poe ie ab reas SNC Cai abe) 
Mg—Magnesia.’. : -.  « 2 
That the molybdenum exists in this mineral as molybdic acid is altogether 
probable from the fact of liquid ammonia acting on it so readily. 
