A SYST'EM OF 
argillaceous vein crolTes the veins of the 
iron, ore, and will perhaps be found to 
have more of thefe riches, even in feve- 
ral other places, if well fearched, as is 
done in other countries, oftentimes not 
on filch evident marks or figns, 
SECT, CLXIX. 
B. DilTolved and rnineralifed, Argentum miner a- 
lifatum, 
I. With fulphur alone, Argentum fulphure 
miner alifatum, Glafs filver ore, Minera ar- 
gent i vitrea. 
This is duflile, and of the fame colour 
as lead^ but, however, becomes blacker 
in the air. It has, therefore, very unde- 
fervedly got the name of glafs ore, for that 
name rather belongs to the minera argenti 
cornea^ or horn filver ore, if indeed any 
filver ore can be confidered as glaffy. 
It is found in the fame manner as na- 
tive gold ; viz. 
1. In crufts, plates, or leaves. 
2. Grown into, 
a. Snaggs, and, 
h. Criftalline figures. 
It is generally either of a lamellar 
or a grained texture, and is found at 
Kongfberg and in the Saxon mines. 
The glafs filver ore is the richeft 
of all filver ores ; fince the fulphur, 
which is united with the filver in this 
ore, makes out but a veryfmall quan- 
tity of its weight. 
SECT. 
