PLATINA ORE OF ST. DOMIXaC t^f 



XIII. 



On the Ore of Platina of St, Domingo : by Mr. Guyton- 



MORTEAU*. 



JLt had long been supposed, that platina was found only in Plaiina report- 

 the gold mines of Santa-Fe and of Choco in Peru. Twenty ^^^^^^^^^^^^ j^ 

 years ago there was a report, that some had been obtained st Domingo 

 from a ferruginous sand in St. Domingo ; but apparently the «ome years ago. 

 examination of this was not executed so as to give decisive 

 results, since it has not been published. The report, no 

 doubt premature, of its existence in Siberia, has likewise 

 died away. The singularity of such a limited and appa- 

 rently exclusive situation remained attached to platina, till 

 Mr. Vauqueiin found as far as 10 per cent of it in the gray 

 silver ore of Guadalcanal ; wherehe has no doubt it is in the 

 metallic state, but without being accompanied with either of 

 the four metals lately discovered in the platina ore of Peruf. 



What Mr. Percy submitted to the inspection of the Insti- This lately »•• 

 tute, on the I2th of Feb. 1810, leaves no doubt of the exist- "^^* 

 ence of this metal in the eastern part of St, Domingo. It 

 was brought thence by surgeon-major Dubizy, an enlighten- 

 ed naturalist. It exhibits precisely the same characters as 

 that we have from Spain. The grains, equally flattened, are 

 »» general a little larger, and its specific gravity is a little 

 greater ; which may arise from its having been more carefully _ 

 freed from foreign matter, though the magnet still separates 

 some from it. It is found, principally after heavy rains, i& 

 the sands of the river Yaqui, at the foot of the mountains of 

 Sibao. These sands, which contain also a little gold, are^ 

 collected by women, who, without washing them, sell them 

 for a few maravedis. 



Mr. Jeannety, who has begun to manufacture a few hec- S»ine goldl 

 togrammes of this ore, informs rae, that, having slightly cal-''^^^"" 

 cined it, and afterward poured on it sulphuric acid, he 

 perceived a few grains of gold among it, 



• Ann. de Chim. vol. LXXIII, p. 334. 



t Ann. de Cnim. vol. LX, p. 31?: or Journal, vol. XVII, p. 128. 

 [Mr. G. M. should also have mentioned tbe ore from Brazil, of which 

 an account is given by Dr. VVoUaston, in the Phil. Trans, for I8O9, y. 

 itg. SeeJouraal, T«l XXV, p. 18. C] 



, SCJENTIFIC 



