Proceedings, §c. li 



A discussion ensued, in which the Rev. Mr. Jarrett and C. W. Ligar, 



Esq., Surveyor-General, took part. 



Dr. Macadam read a paper entitled " On the Manufacture and 

 Chemical Composition of Spurious Gold lately detected in Victoria," 

 and exhibited specimens of the material. He specially directed 

 attention to a variety discovered to have been extensively manu- 

 factured in the neighbourhood of Ballarat, and which had been 

 brought under his notice, as Analytical Chemist to the Government, 

 in a recent criminal prosecution for the offence of vending the 

 spurious preparation for genuine gold. The manufacture had been 

 carried on by a Chinaman, and the mortars, crucibles, furnaces and 

 other appliances, as also portions of the manufactured article in its 

 different stages, were found upon his premises. The alloy consisted 

 mainly of copper, which was present to the extent of neaily 80 per 

 cent., gold 8 per cent., and the rest silver ; each fragment of the 

 alloy had been afterwards successfully coated with a fdm of pure 

 gold, which enabled the spurious article to resist the action of strong 

 nitric acid, either in the cold or heated state, even for the space of 

 24 hours. A few drops of hydrochloric acid, however, to the nitric 

 acid, soon dissolved the protecting gold film, when the alloy was 

 rapidly and powerfully acted on by the nitric acid. To detect such 

 a counterfeit substance, he stated therefore that in future in apply- 

 ing the nitric acid test the addition of hydrochloric acid would 

 likewise be necessary, so that if the gold consisted of a merely 

 superficial coating, that being dissolved, the true nature of the in- 

 closed alloy would be revealed by the usual evolution of the ruddy 

 vapour of nitrous acid gas, and the production of a green solution. 



As the alloy had been covered with pure gold, of course the 

 color of the spurious material was almost unexceptionable. It was 

 rather too bright and lustrous after treatment with nitric acid, or as 

 it was originally made, but a greenish shade, and the characteristic 

 unctuous feel of genuine nuggetty washed gold had been communi- 

 cated by slightly larding the particles. 



The sample could be readdy separated into the results of three 

 different processes, as far as the mechanical part of the manufacture 

 was concerned, viz. : — Gold-dust, shotty gold, and nuggetty gold. 

 A quantity of the spurious material had been separated into 

 these three lands. The gold-dust proved to be an excellent imita- 

 tion, and had, as was manifest from the appliances discovered, been 

 produced by pressing the liquid alloy through a perforated iron 

 cup. The shotty gold had been manufactured in much the same 

 way, but had been allowed, as in the usual preparation of shot lead, 

 to fall from a height, the round particles being afterwards flattened 

 by being struck with a wooden mallet. The resemblance of the 

 product to shotty vjater-worn gold was thus very perfectly secured. 

 The nuggetty or rugged particles were much larger, and had been 

 formed by pouring the alloy from a height into water, as in the 



