436 
Geology . 
disseminated. We have no certain information respecting 
the geognostic situation of the Peruvian gold ; but we 
have much to expect from Humboldt on this curious 
and important subject. The age and geognostic rela- 
tions of the gold-sand of Guinea and Brazil are equally 
unknown. If the views published by the Portuguese 
mineralogist Dandrada be correct, it is probable, says 
Kars ten, that the gold of Brazil will be found to occur 
in a sandstone somewhat older than the independent coal- 
formations.* 
Brass-yellow native gold is confined to the newer por- 
phyry and grey-wacke, where it occurs in veins, as in the 
case in Hungary and Transilvania. It is said also to 
occur in sandstone and bituminous wood. Veins of gold 
also occur in the Uralian mountains ; and these appear 
to occur in old flcetz -limestone. 
16. Sylvan , Tellurium of chemists. — This metal oc- 
curs along with brass-yellow native gold in the newer 
porphyry, and has been hitherto found only in Transil- 
vania. 
17. Antimony .— This metal is found in all the Hun- 
garian and Transilvanian gold mines, and hence it oc- 
curs in newer porphyry and grey-wacke. The oldest 
formation occurs in beds with iron-pyrites and quartz at 
Schmolnitz in Hungary, and appears to be cotemporane- 
ous with that found with green garnets in Norway. It 
occurs in veins that traverse grey-wacke in the county of 
Dumfries. 
18. Manganese *. — This metal occurs in veins in old 
primitive rocks, but most abundantly in numerous small 
veins that traverse the newer porphyry, and in veins that 
traverse grey-wacke. According to the late observa- 
tions of Karsten, it occurs, along with beds of ironstone, 
* Gold-yellow native gold has been found inf veins along with 
quartz and iron-pyrites, but the age of these veins is not known-. 
