525 



the lodes and indications of ores, which we 

 found in the mountains of gneiss. No regular 

 trials having been made, we could only examine 

 the fissures, the ravins, and the fallings down 

 of the earth occasioned by the torrents in the 

 rainy season. The rock of gneiss, passing some- 

 times * into a granite of new formation, some- 

 times mica-slate, belongs in Germany to the 

 most metalliferous rocks ; but in the New Con- 

 tinent, the gneiss has not hitherto been re- 

 marked as very rich in ores worth working. 

 The most celebrated mines of Mexico and Peru 

 are found in the primitive and transition schistus, 

 in the trap porphyries, the grauwakke, and the 

 alpine limestone -f-. In several spots of the 

 valley of Caraccas, the gneiss contains a small 

 quantity of gold, disseminated in small veins of 

 quartz, sulphuretted silver, azure copper ore, 

 and galena ; but it remains doubtful, whether 

 these different metalliferous substances are not 

 too poor, to merit any attempt at working them. 

 Attempts indeed were made at the conquest of 

 the province, toward the middle of the sixteenth 

 century. 



From the promontory of Paria to beyond Cape 

 Vela, navigators had found ornaments of gold, 

 and gold dust, among the inhabitants of the 

 coast. They penetrated into the interior of the 



* Especially at great elevations. 

 + Nouv. Esp., vol. ii, p. 494. 



