TRAVELS IN BRAZIL. 



by black dendritic manganese, contains gold ; but 

 in this mine they work only the quartz veins (veas, 

 Jiloes), To uncover the latter, the owner has had 

 the mountain washed away in many places by 

 means of a strong current of water, and thereby 

 made so many steep ravines in the already soft 

 rock, that he can scarcely continue to work the 

 veins farther, without danger of their falling in. 

 It would have been more advisable to commence 

 a regular work, with adits and shafts lined with 

 planks. The gold obtained here is generally two- 

 and-twenty carats fine. 



In the evening we visited the mine called Cuja- 

 beira, now abandoned, where the chromate of lead 

 was discovered. It is in a field scarcely a league 

 from the fazenda of Senhor Monteiro, in a low hill 

 of clay, which, on the whole, runs from N.N.W. 

 to S.S.E. We in vain searched among the debris 

 to find a few tolerably large pieces of this scarce 

 fossil, till the colonel conducted us to a small adit 

 which he had just opened. Here we had the plea- 

 sure of observing the red lead-ore in a vein of 

 friable greyish white granular quartz, among pretty 

 much disintegrated, white, scaly lithomarge, of the 

 thickness of a few inches to a foot, running from 

 north to south. The quartz, which forms the ma- 

 trix, is here and there of a lemon colour, and 

 traversed with brown oxyde of iron. The crystals 

 of the chromate of lead are small and very small, 

 and seldom show well-defined terminal planes, 



VOL. II. T 



