aha The ease Wee eS ty 
Pe ea eee ar Peete ena ee er SS ee ee ev 
Puree june aia, : Z e i 
B. Silliman— Mineralogical Notes. 201 
a trace of arsenic from the included crystals in the calcite, 
when tested by soda and potassium cyanide i in the closed tube. 
This quartz carries crystals of vanadinite*’in habit very unlike 
those which occur at the Hamburg mine in the Yuma district; 
they are long slender needles hardly a line in thickness, of a 
delicate straw-yellow color, quite transparent. They are asso- 
ciated with others of a rich orange-yellow color and not so 
well defined, There are also confused tufts of erystals of the 
same species, not thicker than hairs, of a pure chrome-yellow — 
color, implanted in cavities in the red iron-stained gangue. 
Descloizite (?}—A mineral which may prove to be descloizite, 
semi-transparent and very brilliant crusts, the individuals im- 
perfectly developed; hardness about 3— 35; ; streak-yellow to 
brownish-yellow. Alone in the closed tube it fuses and gives 
off abundant water. It Piya very strongly for vanadium and 
for lead, also for copper, manganese and zinc. Since this paper 
was in hand I have ie from Mr. Farley, under date of 
June 25th, additional specimens of this mineral not only from 
the “<Collater al” but also from the ‘‘Chromate” veins near the 
former, on one of which are seen very well defined, but very 
parent and of a clear olive-green. The luster is vitreous and 
ull. No erystals were detected. Alone in the matrass it fuses 
readily, adhering to the glass. It gives off no water and dis- 
solves in dilute “hydrochloric acid to a greenish solution from 
which alcohol throws down the lead in tufts of plumbic chlo- 
ride. On charcoal it fuses to a black shining bead which 
alone gives off lead fumes and copper appears on crushing the 
bead in the agate mortar. With soda it gives a globule of 
lead enclosing one of copper. Zinc oxide stains the coal when 
the assay is gently heated. It may be that it will turn out to 
be a new specie 
An anhydrous cryptocrystalline mineral containing vanadi- 
occurs among the “ Collateral” ores. It varies in color from 
light yellow-brown to black-brown; gives the reactions for 
* Monatsbericht der Akad. zu Berlin, July, 1880, 672. 
