C. U. Shepard, Sr.—Mineralogical Contributions. 95 
existing together in small quantity, associated with chrysoberyl, 
yellow beryl, columbite, garnet and a zircon mineral which I 
afterwards called calypto olite. Mr. Ames has lately procured 
of the meeting- house. They ad etre formed a narrow 
seam in the common orthoclase granite, which had been opened 
with a view to working as a porcelain-feldspar quarry. One of 
the specimens weighs about half a pound; and constitutes a 
deeply striated or channeled crystal. The mineral was supposed 
to be molybdenite. Examined before the id -pipe, it affords 
no indications either of tellurium or seleniu 
4. On the metallic acid in Microlite. 
It having been suggested by Prof. Brush, from blow-pipe 
experiments* and the higher percentage of the metallic acid in 
this mineral, that it is the tantalic instead of the columbic, 
made the following experiments upon two small crystals whose 
weight together was 0350 gram. It was decomposed by 
fusion with bisulphate of potash, cold water dissolved the mass, 
which afterwards deposited a white granular precipitate, the 
clear supernatant — not showing even an opaline tendency 
on ebulition. The white precipitate after ignition gave 72°80 
P. ce. for the metallic acid. It evinced scarcely the ce 
opeaty. No tinge of violet or pink is visible. 
F the metallic acid afforded a bluish gray 
The es of alkali — removed by cold water, the 
iduum. A portion 
this solution on ban skdiioted with hydrochloric acid, and 
afterwards treated with solution of nutgalls, gave a very yellow 
i that prod lum. 
th 
chief } ion of the sbi solution was then super- 
ot ep — acid, and gave rise to a decided 
* Dana’s Mineralogy, a 
+ There was a want 0: corresponden ce also in the reactions of the metallic acid 
poe soda a pe with nce Enis of one nitrate of mereury, corrosiv iS iebiiate 
