84 W. Mallet, Esq., on the Minerals of the 



to the finest grain tin.* 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 ob- 

 tained, it would probably richly repay the labour and ex- 

 pense of its collection and smelting. From the small quan- 

 tity 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 separatingit from the rest of the sand ; 

 and the almost total absence of arsenic and lead would ren- 

 der it extremely easy to obtain from it metallic tin of the 

 very first quality. The mineral itself occurs in grains vary- 

 ing in size from fine sand up to pebbles of half an inch in 

 diameter, and in the most part of a dark brown colour, with 

 some fragments of various tints of yellow and red ; some 

 presenting the peculiar appearance 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 with a 

 short four-sided prism interposed between the two py- 

 ramids, and the latter of these with various truncations of 

 its angles and edges. The specific gravity of some picked 

 crystals was 6'753. A careful analysis of this tinstone gave 

 as its constituents — 



Peroxide of tin, . . . 95-26 



Peroxide of iron, . . . 2-41 



• Silica, . . . . -84 



98-51 

 The greater number of the minerals here enumerated are 

 mentioned by Mr Weaver in his reports to Government on 

 the district, and which are to be found in the Transactions of 

 the Royal Dublin Society ; but some of them, the author be- 

 lieves, have not been noticed before, at least he has seen no 

 published account of the occurrence in this locality of platina, 

 titanic iron, sulphuret of molybdenum, topaz, zircon, the small 

 magnesian garnets, or augite. Hence it seemed interesting. 



* 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 scoria;. 



