﻿British Mineralogy. 325 



The results of these two analyses are given as follows : — 



Gold .... 

 Silver . . . 

 Iron .... 



Mallet. 



9232 



6-17 



0-78 



Scott 



89-0 



8-1 



21 





99-27 



99-2 



Specific gravity . 



16-342 



? 



Several large nuggets of the gold from the washings on the 

 river on the north-east side of the mountain Crogban Kinshela 

 in the county of Wicklow, on the borders of Wexford, are to be 

 seen in the British Museum ; and the largest nugget known to 

 have been obtained is stated to have weighed twenty-two ounces. 



The minerals associated with this gold are as follows : — 



Cassiterite (tinstone), magnetite, hsematite, pyrite, titanoferrite, 

 wolfram, wad, chalcopyrite, galena, molybdenite, garnet, chlo- 

 rite, felspar, and mica — as well as, according to Mr. Mallet, 

 topaz, sapphire, zircon, and native platinum. 



This gold is, without doubt, derived from the disintegration 

 of the granite of the district, which appears to be what I have 

 elsewhere described as a normal auriferous granite composed of 

 orthoclase, quartz, and mica, similar to the Cornish rock, and, 

 like it, both stanniferous and auriferous. 



That the gold along with the cassiterite and wolfram really 

 exists as a constituent of the granite itself, or, in other words, 

 is disseminated throughout its mass, is in accordance with the 

 conclusions arrived at by Mr. Weaver, who, with Messrs. Mills 

 and King, was appointed Director of the Government gold-wash- 

 ings on the Ballinvally stream at Crogban Kinshela in 1796. 

 The observations of Mr. Weaver are contained in the report on 

 the geological relations of the east of Ireland, published in the 

 Transactions of the Geological Society, vol. v. p. 211; and he 

 mentions therein that the total gold obtained during the period 

 that the washings were worked on account of the Government 

 amounted to 944 ozs. 4dwts. 15 grs., or in value £3675 7s. 1 lid., 

 and that up to the time of the Irish Rebellion in May 1798 the 

 gold obtained had not only fully reimbursed the advances made 

 by the Government, but had, besides defraying its expenses, left 

 a surplus in hand. 



Native Gold, Sutherlandshire. 



In the sixteenth century gold is said to have been discovered 

 in some quantity, and w T orked, at Durness on the north coast of 

 Sutherlandshire ; and in 1840 a solitary nugget of more than one 

 ounce in weight is reported to have been found in the river of 



