A SYSTEM OF 
a* Uncoloured and clear, Biaphnmm. 
Is found in the copper mines in the 
north part of Norway, and in Siberia. 
This has no criftalllfed form, but is ne- 
verthelefs as clear as quartz criftals of 
the beft water. 
i. White, the common fat quartz. 
c. Blue, from the ifland of Uto in the 
province of Sodermanland. 
d. Violet, from the ifland of Uto. 
S. Grained, "Bextura granulata, 
a. White, from the gold mines at Adel- 
fors in the province of Smoland, and 
the copper mines at Lovifeberg in Well- 
manland. 
h. Pale green, from Adelfors. 
C. Sparry quartz, T extura fpatofa. 
This is the fcarceft, and ought not to 
be confounded with the white Felt-fpat 
Sedi. Ixvi. being of a fmoothef appear- 
ance, and breaking into larger and more 
irregular planes. 
a. Whitifli yellow, from the gold mines 
in'Hungary. 
White, from the ifland of Uto. 
SECT. LIT. 
D. Criftallifed Quartz, ^arzum criftallifa- 
turn. Rock criftal. Quartz crifliaL Crif- 
talks montajius. 
Its figure is already (Sed. L) defcrib- 
ed, and, in regard to the colpurs, the fol- 
/ lowing varieties occur. 
I. Opaque, or femi-tranfparent, Crift alius 
opacus vcl femi-diaphanus. 
a. White, or of a milk colour. 
( 
b Red 
