430 
Geology . 
the tin-stone formations, excepting that which contains 
schorl. In these situations, it is found in England, Sax- 
ony, Bohemia, and probably also France. In the Hartz, 
it occurs without tin-stone, in great veins, that traverse 
grey-wacke ; constituting, however, but a small portion 
of these veins. It never occurs in newer rocks ; and the 
instance we have just mentioned, of it occurring in grey- 
wacke, is only an exception to the rule, that wolfram is a 
very old formation of the primitive period. 
Tungsten , the other ore of scheele, occurs only in pri- 
mitive mountains, and in different tin formations. This 
is the case at least in Saxony, where it is found in most 
considerable cfuantity. The geognostic situation of that 
found in Sweden is unknown. Like wolfram, it does 
not occur in that particular tin formation which is accom- 
panied with schorl. 
5. Cerium .— This metal occurs imbedded in wolfram ; 
hence is of equal antiquity. 
6. Tantalum . — This appears also to be a very old me- 
tal. It is nearly allied to tin. Its geognostic situation 
has not hitherto been ascertained with perfect accuracy. 
It would appear to occur in felspar-veins that traverse old 
mica- slate ; hence it is to be considered as of cotempora- 
neous formation with it. One species, the Tantalite, oc- 
curs in the parish of Kimito in Finland ; the other, the 
Ytter tantalite, at Ytterby in Sweden. We may remark, 
however, that the geognostic situation of the Yttertanta- 
lite is not well known ; the geognostic situation just 
mentioned is that of the tantalite, 
7. Ur an . — This metal occurs only in primitive moun- 
tains. Pitch-ore, uran- ochre and uran-mica, occur to* 
gether in veins of a pretty old formation that traverse 
gneiss ; but uran-mica occurs principally in ironstone- 
veins that traverse granite and other primitive rocks. 
