The ^'■Aif(/eit'''-(.rnei.ss Area. — LiKiuev a ml /ties. 248 
In these pegmatite areas the colors of the quartz and feld- 
spar vary considerably. Rose, white and smoky quartz are 
found; while the feldspar varies from dark red to almost 
white, which loss of color seems to be due to kaolinization, es- 
pecially near the surface. -'Perthitic'' intergrowths of feld- 
spar are noticed in P. H. Kinkel's (juarr3\ 
The two following analyses of feldspar from P. H. Kinkel's 
quarry show it to be high in potash, witli practically an ab- 
sence of lime. The feldspar seems to be chietiy orthoclase, 
although many evidences are shown inicroscopically of micro- 
clinic structure. 
I 
II 
SiO., 
64.97 
6.5.85 
Al.p, 
20.85 
19.32 
Fe^Oa 
tr. 
.24 
K.,b , 
13.72 
[ 14.10 
H.,0 
(by loss) 
.46 
CaO 
.56 
MgO 
.08 
100.00 100.15 
No. I. Furnished by P. H. Kinkel. 
No. II. "Chemistry of Pottery" p. ;iS. ('. Latiffenbecli. Anal. 
Unfortunately no contacts of the quartz and feldspar with 
the porphyritie or "augen"-gneiss were obtained, as the exca- 
vation has always stopped when the minerals became too 
mixed to be of commercial value. So far as the surface out- 
crops go, the change to the surrounding rock seems to be 
gradual and there is no evidence of an irruptive contact be- 
tween the pegmatite and the "augen"-gneiss. 
In the southeastern portion of L. McDonald's quarry (A) 
there occurs a steep wall of biotite-hornblende schist, some- 
what decomposed and forming an abrupt bounding wall to the 
pegmatite. The dip is very steep and the strike S. 30° W. 
There are very few good contacts with the schist to be ob- 
served, as the quarrying has not been pushed that far on 
account of the impuritie^s encountered. At one place, however, 
near the mouth of the excavation a very sharp contact can be 
seen. A section of this contact showed the pegmatite to con- 
sist of quartz, plagioclase and orthoclase, the latter containing 
plentiful hematite inclusions and, near the contact, enclosing 
small rounded grains of quartz. The contact under the mi- 
