42

Prare V.

A. Mierophotograph of polished ore from No. 2
vein of the Rocher De Boule mine, magnified 200
diameters. Chaleopyrite veining and replacing tetra-
hedrite, and both cut by veins of quartz. The sul-
phides are considered to be of the first mineralization
and the quartz is probably of the second. 1, tetra-
hedrite; 2, chalcopyrite; 3, quartz. (Page 12.)

B. Mierophotograph of polished ore from No. 2
vein of the Rocher De Boule mine, magnified 200
diameters. Arsenopyrite of the second mineraliza-
tion replacing chalcopyrite of the first. 1, chalco-
pyrite; 2, arsenopyrite; 3, quartz. (Pages 12, 13.)