1854.] CHARTERS — GEOLOGY OF NICE. 35 



Thames, a continuation of the same range, at a distance of 45 miles 

 from Coromandel. 



Relations of the gold to its matrix, and to the deposits in which it 

 is found. — Where large quartz boulders appear denuded on the surface, 

 gold is generally found in the black sand (Specimen K.) of the ad- 

 jacent stream. When the gold is found in clay, it is generally in con- 

 tact with a fragment of the matrix — a brittle quartz, of a grey or 

 amethystine colour. When found in the stream, it is either in pure 

 scales (Specimens O.), or associated with a quartz (Specimens I.) 

 coloured red, apparently by the oxide of iron. It is probable that 

 this combination imparts to it that degree of hardness which causes 

 the stone to withstand the crushing action of the rolling stones of the 

 stream-bed. The purer gold found may have been freed from its 

 more brittle matrix by the attrition. 



The gold is but rarely found in contact with the prismatic crystals of 

 the quartz. It is generally ramified with but little regularity through 

 the mass. In some cases where it lay between lamellar plates of 

 quartz it was the richest. In larger fragments (Specimens L.) of the 

 stone the gold existed only in spangles at a distance of an inch or 

 more apart. From this and from other indications presented by the 

 matrix, I infer that the gold in a quartz-vein is diffused where the 

 vein is broad, and concentrated where it is narrow ; the quantity of 

 the metal existing in a similar length of the vein under either circum- 

 stance being perhaps the same. 



The extent of the surface of ground that has been dug over is 

 about 1500 square yards. The depth from which the gold has gene- 

 rally been taken is from 4 to 6 feet. 



The total quantity of gold which has been obtained may be esti- 

 mated at 340 ounces, the chief part of which has been extracted from 

 an auriferous quartz yielding a mean of one-third of its weight of 

 metal. 



From the very general diffusion of small particles of gold over the 

 surface of the district, experienced *' Prospectors" are of opinion that 

 a large quantity of matrix-gold exists in the mountains adjacent to 

 the diggings. The dense forest and its tangled undergrowth are great 

 hindrances, however, to the exploration of the country ; and the large 

 amount of water which, from the moist climate of New Zealand, is 

 everywhere present, together with the looseness of the rock where 

 the gold is found, have prevented the examination being carried to 

 those depths where in the Australian and Californian Gold Fields the 

 gold most abundantly exists. 



3. On the Geology of the Vicinity ©/"Nice. 

 By Major Charters, F.G.S. ' 



[This Paper was withdrawn by permission of the Council.] 

 (Abstract.) 



The author, having first alluded to the geological researches of Sir 



H. De la Beche * in this district, noticed the more recent additions 



* Trans. Geol. Soc. 2nd ser. vol. iii. p. 171 et seg. 



D 2 



