S. L. Penfield—Occurrence of Alkalies in Beryl. 2% 
StOPr*. Se ooo Pe ee oe 42°56 
Sulphurio atid 22... cee. 34°43 
VEIN b Ss ge ae 15°52 
Peso... ooo eee 7°62 
100°13 
The following minerals from new localities have also come 
under our observation, and may be properly noted here. 
Vivianite from Washington, D. C. Found abundantly in a 
bed of blue clay, during excavations for the foundation of a 
building on Connecticut Avenue. The mineral occurs in blue, 
earthy masses. 
yalite from Foster's mica mine, near Jefferson, Ashe 
County, N. C. In very fine stalactitic form, coating the under 
side of a quartz shelf in a broad granite vein. The specimens 
are tinted with ferric oxide, and are as fine as any yet noted in 
this country. 
Beryl from Gilmore’s mica mine, in Montgomery County, 
Md., twelve miles north of Washington. Abundant, but not 
well crystallized, and associated with albite, large plates of 
muscovite, quartz, garnet and black tourmaline. 
Cassiterite from the Brewer Gold Mine, Chesterfield County, 
. C. Found in some quantity in the “black sands” of the 
gold washing, and crystals of 4” in diameter have been col- 
_ lected. The larger crystals are dark colored, while the small 
ones are often pale brown, straw-yellow and even colorless. 
The latter jn microscopic grains. 
Washington, April 14, 1884, 
Art. IV.—On the occurrence of Alkalies in Beryl; by 
SAMUEL L. PENFIELD. 
. 
further examination was made and the mineral was proved to 
be beryl. In calculating the first analysis the small quantity 
of alkalies, five per cent in all and more than half czsium, 
and the great preponderance of sesquioxides made it probable 
that the mineral was either impure or that some protoxide was __ 
present which the alkalies could be regarded as replacing. : 
* 
