Mineralogical Notices. 227 
a vitreous lustre. The greenish crystals are less hard and prob- 
ably have undergone some alteration by infiltration. The min- 
eral from Quenast afforded 
Si xl e Mn Mg- Oa *Na K 
6370 2264 058 trace 120 144 615 281, ign, 1:22=99°69 
Delesse thence concludes that the feldspar is an oligoclase. The 
feldspathic paste of the porphyry contains some more oxyd of 
iron and magnesia than the crystals of feldspar, and Delesse dis- 
tinguished minute crystalline plates disseminated through it, 
which appeared to be chlorite. ‘The chlorite becomes of a bronze 
color after calcination. 
The rock of Lessines affords crystals of axinite and epidote, 
besides quartz in crystals, and calcite. The porphyry taken asa 
whole afforded on analysis | 
Si Al, Fe Oa Mg, alkalies, Hand € 
57-60 25-00 3-23 9°92 4-25=100. 
The proportion of silica is hence small, much below that of the 
d 
oligoclase above described. 
Analysis of Wollastonite from Auerbach, by F'. L. Winckler, 
(Jahresb. f. pr. Pharm., xviii, 317, 
Si Ca and trace of Mg 6 H #e, Mn 
530 45-40 1-0 0-6 
On the Variolite of La Durance; by M. Deuesse, (Ann. des 
Mines, 1850, [4], xvii, 116.)—The variolite consists of globules 
stand out on its surface. They are often of a violet shade within 
56-19 —. Fe €r Hin = Ga Mg Na 
719 O51 trace 874 S841 3°72 
They are properly therefore a feldspar, although it is difficult to 
determine certainly the species ; as there is a euphotide in contact 
With the rock, Delesse suggests that it is probably the same with 
* 
K 
0-24, ign. 1:93==99°86 
the feldspar of the Euphotide of Odern. 
PNB orca ee 
* This Journal, [2] x, 252, and Ann. des Mines, [4], xvi, 323. 
