' Natural Hktonj, 225 



7. Native Argentiferous Gold. — M. Boussin^ault, who has had the 

 opportunity of examining numerous specimens of argentiferous 

 native gold from the Columbian mines, thinks that they are atomic; 

 he has found 1 atom of silver imited to 2, 3, 5, 6, and 8 atoms of 

 ^old, and considers it probable that the other combinations to com- 

 plete the series may occur. He has assumed 24.86 as the number 

 for gold, and 27.03 as the number for silver. The following are 

 some of the experimental results : — 



Native Gold ofMarmato. — Pale yellow octoedral crystals ; 



Native Gold ofMalpaso. — Yellow irregular flattened grains ; 

 Gold . . 88.24 8 atoms . 88.04 

 Silver . . 11.76 1 „ . 11.96 



Native Gold of Rio-Sucio, — Deep-coloured large irregular grains : 

 Gold . . 87.94 8 atoms . 88.04 

 Silver . . 12.06 1 „ . 11.96 



Native Gold of the Otra Mina. — Pale yellow octoedral crystals: 

 Gold . . 73.4 3 atoms . 73.40 



Silver . . 26.6 1 „ . 26.60 



Native Gold of Guamo. — Brass-yellow indeterminate crystals: 

 Gold . . 73.68 3 atoms . 73.40 

 Silver . . 26.32 1 „ . 26.60 



Native Gold of Llano. — Small flattened grains — reddish: 



atoms . 88.04 

 „ . 11.96 



atoms . 88.04 

 11.96 



Native Gold of Ojas-Anchas.—'Y^\\ovf\s\i red plates : 



Gold . . 84.5 6 atoms . 84.71 



Silver . . 15.5 1 „ . 15.29 



Native Gold of Trinidad, near Santa Rosa de Osos. — ^A solid piece 

 of 50 grains: 



Gold . , 82.4 4 atoms , 82.14 



Silver . . 17.6 1 ,» • 17.86 



Native Gold of Transylvania (Europe). — Pale yellow cubic crystals: 

 Gold . . 64.52 2 atoms . 64.77 

 Silver . . 35.48 1 „ . 35.23 



Native Gold of Santa Rosa de Osos. — A mass weighing 710 grains : 

 Gold . . 64.93 2 atoms . 64.77 

 Silver . . 35.07 1 „ . 35.23 



M. Boussingault has remarked u singlar deficiency in the 

 JULY— OCT. 1827. Q 



