Intelligence and Miscellaneous Articles, 393 



which characterize the metal, and, owing to the attrition to which it 

 has been subjected, generally presents a beautifully brilliant surface. 

 It occurs in grains of all sizes, from the smallest spangle up to a 

 mass weighing twenty-two ounces, the largest hitherto found. The 

 specific gravity of some small grains Mr. Mallet found to be 16*342. 

 The analysis of these grains gave — 



Gold 92-32 



Silver 6-17 



Iron -78 



99-27 



This is equivalent (neglecting the iron) to 8^ atoms of gold and 1 

 of silver. 



Platina. — Mixed with the gold are some very small flattened 

 grains of a white colour and metallic lustre, which, as far as their 

 minute size permitted an examination, appear to present all the 

 characters of platina. They are infusible before the blowpipe, and 

 insoluble in nitric acid, but dissolve in aqua-regia. Their occurrence 

 intermixed with the gold when all other minerals have been washed 

 off, is a proof of their high specific gravity*. 



Tinstone. — The occurrence of this mineral in the sand is men- 

 tioned by Weaver in his reports on the gold-stream-works, but he 

 does not seem to have been at all aware of the large quantities in 

 which it exists. From the comparatively small portion f of sand 

 which the author had an opportunity of examining, he obtained 

 about 2>\ pounds of stream tin ; a portion of which being reduced, 

 yielded an ingot, which, when refined by a second fusion, is hardly 

 inferior to the finest grain tin J. Should this mineral be found in 

 the mass of the sand in a quantity at all approaching that in which 

 it existed in the specimen from which this was obtained, it would 

 probably richly repay the labour and expense of its collection and 

 smelting. From the small quantity in which other minerals of high 

 specific gravity exist in the sand, and the constant supply of water, 

 very little difficulty would be experienced in separating it from the 

 rest of the sand ; and the almost total absence of arsenic and lead 

 would render it extremely easy to obtain from it metallic tin of the 

 very first quality. The mineral itself occurs in grains varying in 

 size from fine sand up to pebbles of half an inch in diameter, and 

 for the most part of a dark brown colour, with some fragments of 

 various tints of yellow and red ; some presenting the peculiar ap- 

 pearance to which the name " wood tin " has been given. All these 

 varieties are slightly translucent, some of them highly so. Many 

 of them present distinct traces of the obtuse octohedron, the same 



* It is to be wished that the existence of platina had been more fully 

 ascertained. — Ed. Phil. Mag. 



f The exact weight of the specimen examined the author does not know, 

 but thinks it certainly did not exceed 150 lbs. 



X The specimen smelted in this experiment yielded about 61 per cent, 

 of tin; but more would be obtained on the great scale, as in this case no 

 pains were taken to extract the tin remaining in the scoriae. 



