434 E. Hussak, 



to consist. Itb appearence was such indeed, as at first sight to 

 induce a suspicion of its not being in a naturale State, for it had 

 veiy much the spongy form, which is given to platina from 

 imperfect attempts to render it malleable by means of arsenic. 



One circumstance, howewer, occasions a presumption, 

 that no art has been employed in giving the grains their present 

 appearence, as upon close inspection many small particles of 

 gold are discernible, but there is none of the magnetic iron- 

 sand, vvith which the Peruvian ore abounds, nor any of the 

 small hyacinths, which I have formerly noticed as accom- 

 panying that mineral. 



It is ver}^ well known, that the common ore of platina in 

 general consists of flattened grains, that appear so much worn 

 at their surface, as to be in a considerable degree polished, and 

 the roughness observable in some of the 'arger grains arises 

 from concave indentations of a reddish brovvn or black colour. 



The Braz ilian Platina, on the contrary, has no polish, 

 and does not appear worn, but most of the grains seem to 

 be small fragments of a spongy substance, and even 

 those which are 3'et entire and rounded on all sides, present 

 a sort of the former, as their surface consists of small 

 spherical protuberances closely coherent to each other, 

 with the interstices extremly clean, and free from any degree 

 of tarnish.« 



Diese überaus zutreffende Beschreibung des brasilianischen 

 Platins von Wollaston stimmt, wie weiters gezeigt werden 

 wird, vollkommen mit dem Vorkommen vom Corrego das 

 Lagens und Serro überein. Schon hier möge bemerkt werden, 

 daß ein ähnliches Platinvorkommen noch nicht bekannt ist. 



Wollaston fand in diesem Platin kein h'idium, die An- 

 wesenheit von Palladium blieb zweifelhaft, nur eine Spur Gold 

 wurde nachgewiesen. 



Der erste, der genaue Angaben über dieses brasilianische 

 Platinvorkommen nach Studien am Fundorte selbst gab, war 

 1812 der Reisende Mawe — er fand dasselbe in den Fluß- 

 sanden des Corrego das Lagens (»Largos«), zwischen Itam- 

 bedo Alatto-Dentro und Conceicao, Municip d. Serro »Minas 

 Geraes«. 



