332 W. F. Fontaine—Minerals in Amelia County, Va. 
found. One of them, which is not the largest, is in the form 
of a rectangular prism, formed of the faces O and 72 much pro- 
tonged. It has at one end several prismatic faces, while the 
other end is broken, since it formed the place of attachment. 
This crystal is 50 centimeters long, while the cross-section 
shows in one direction the dimension of 224 centimeters, and 
in the other 20 centimeters. 
Pit No. 1 shows but little feldspar other than orthoclase, but 
a considerable amount of albite occurs in pit No. 2. The 
larger part of this albite occurs in forms that I have seem 
assumed sometimes by stalagmitic deposits when they fill up 
vertical crevices in limestone, and there is little doubt but that. 
this albite results from a secondary deposition of material, that 
made its way into an open crevice in the mass of material first 
deposited. This albite, for a depth of over twenty feet, formed 
a portion of the deposit composed of a closely-interlocked_net- 
work of plates of a beautiful bluish-white material. Often 
angular cavities and cells were left from the incomplete filling 
of the space. At the bottom of this cellular mass, an open 
where. Numerous crystals of smoky quartz lined the walls of 
this cavity along with pure white crystals of albite, some aS 
transparent as glass. The quartz has often mingled with 164 
greenish powder that is evidently a decomposition product. 
The minerals found here were evidently‘deposited after. the for- 
mation of the mass of granitic material, forming the bulk © 
the vein. 
_A small amount of labradorite occurs dispersed in a porphy- 
ritic manner in the masses of orthoclase. It is usually of @ 
smoke-gray color, and sometimes shows a slight change of color 
on turning the specimens. 
A considerable amount of amazon stone is found, but most 
of it occurs in pit No. 2. It ranges in color from bluish-gree™ 
