A New Mineral from the Azores. 33 
Fracture vitreous—no trace of cleavage. The largest crystal 
is only 14 lines at the base of the pyramid. 
With borax on the platina wire, the crystals in the hottest re- 
ducing flame dissolve with extreme slowness and difficulty ; the 
globule is quite transparent, sometimes exhibiting a very faint 
greenish tint. When the globule is saturated with the mineral, 
it becomes opake white by flaming. On the addition of peroxyd 
of iron to the globule, it gives the usual green color of a fer- 
becoming apparent ; this indicates a trace of uranium. 
The powdered mineral is decomposed on fusing with bisulphate 
of potash, and the addition of hydrochloric acid precipitates co- 
lumbic acid. On removing the acid liquor by the filter, and im- 
mersing in it a crystal of bisulphate of potash, flocculent crystals 
of sulphate of lime appear. qe 
The mineral, therefore, like Pyrochlore, is a columbate of lime, 
but as there can be no doubt that this latter is a regular octa 
combination of some of the other ingredients of Pyrochlore, or 
from this new mineral being columbic acid in a different state of 
saturation by lime, from that in Pyrochlore. Either of these 
cases is of much interest to the chemist and mineralogist, and 
I regret that the quantity found is so small as for the present to 
preclude regular chemical analyses of this beautiful though mi- 
croscopic mineral. It seems most probable, as far as we can judge 
from the examinations, that it is a case of dimorphism. Sede 
‘The characters of Pyrrhite before the blowpipe were examined 
at the same time, and confirm my previous opinion of its titanic 
Composition. On the addition to its solution in the borax globule 
of a portion of peroxyd of iron, it gives the usual reddish brown 
glass indicative of titanium. ay” Es 
Iam indebted to my friend Dr. A. A. Hayes, for a careful ex- 
amination and confirmation of the blowpipe characters, as well 
as for the chemical reactions. : 
ere i reat a similarity in the occurrence of this crys- 
tallized columbate of lime in the volcanic boulders of the Azores, 
Econp Series, Vol. 11, No. 7.—Jan., 1847. ) 
