W. F. Fontaine—Minerals in Amelia County, Va. 337 
They are octahedrons, modified by small faces of O, J, and 
mm. All the faces of the same form are not always present, 
and when present, they are usually not equally developed. 
The largest single crystal that I have seen is slightly distorted. 
The longest axis has the dimension of 44. In the direction of 
onazite—Monazite has been found nowhere except at pits 
land 2. It oceurs much as the microlite does, and is often so 
much like it that it requires close inspection to distinguish the 
two minerals. It exists usually in larger masses than the 
microlite, and what is peculiar, never in single or small crys- 
tals. The masses, however, are aggregations of distorted erys- 
tals, and often show on the constituent parts, well-form 
The fracture is very uneven 
Means to distinguish it from microlite. The large masses are 
often formed by the aggregation of imperfect flattened crystals, 
mon One is yellowish 
brown, and the other dark grayish brown. In the mineral 
With the latter color, numerous fine particles of silvery-white 
mica are often found. Besides the above, an orange color is 
Sometimes seen. The different colors often occur together, the 
same specimen showing them in different parts. This mineral 
does not seem to have formed one of the later deposited ones, 
4s it is not found in the cavity associated with albite, ete. The 
monazite is decidedly more prone to aiteration than the micro- 
lite. It is sometimes found with an earthy texture, having 
lost its luster and become more gray in color. 
rofessor G. A. Koenig first recognized monazite among the 
Amelia minerals. For his analysis, see Proc. Acad. Nat. Sci. 
. Jour. Sc1.—Turep Series, Vou. XXV, No. 149.—May, 1883. 
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