25S 
A SYSTEM OF 
Potters lead ore, with limeftonejr 
flate-kernels andfliells, from Gragruf- 
van at Boda in Rettwik, and in Da* 
lame. 
Yellow or marcafitical copper orCj, 
with fmall pebbles. 
SECT. CCLXXVIir. 
2. Of fmaller pieces, Granulis Japidum et 
minerarum, 
a. Potters lead ore with a qnartzofe 
fand, from EifFelsfeidt near Cologn iii 
Germany. 
h. Mountain green with fand, from Si« 
beria. 
r. Cobalt ore with fand. 
d. Martial ochre with fand 
S E C T. eCLXXIX, 
Observa-tions on the Sax a or Stones., 
Befides the advantages which may accrue to- 
ceconomy by a perfedl knowledge of the Saxa, the 
miners or lubterranean geographers expedt alfo» 
* The Mineral Ayencccecs or Sand-ores, cannot reafonably be- 
feparated from the fand-ftones, fince they are produced in the 
fame manner ; befides, when they are poor in yield, they are 
alfo employed to the fame purpofe, becaufe it is not eafy to* 
fmelt the metal out of them. The fand-ores, belrdes, 'cannot 
be ranked in a mineral fyilem as feparate fpecies of ores, be- 
caufe they would then be arranged with refpe6l to the kind of 
Hone in which the ere occurs, and not the ore itfelf, which 
cafe cannot be admitted here. It might be urged, that ores^ 
mixed with the hones of the very load,, and not in form of 
fand-ores, ought as well as them to be ranked among the com- 
pound faxa ; but in that cafe there would be no end of fpecies, 
nor could they ever be reduced into any order. 
another 
