C—2.

It will be seen that these ores are mostly of a very refractory character, and the result of trials on the same scale as you have seen to-day is as follows, as per assay by Messrs. Johnson, Matthey, and Co.: "We have examined the samples of slags marked as under, and find the following to be the result (per ton of 20cwt. of slag) : — Gold. Silver. Oz. dwt. gr. Oz. dwt. gr. No. 1. Queensland ... .. ... 0 7 0 ... 0 4 0 No. 2. „ ... ... ... 0 6 12 ... 0 3 0 No. 3. General Exhibition ... ... 0 3 6 ... 0 3 0 No. 4. „ „ and Never Never 0 5 0 ... 0 4 0 No. 5. Never Never ... ... ... 0 6 12 ... 0 5 0 No. 6. New England ... ... ... Traces ... Traces No. 7. „ and General Exhibition 0 1 12 ... Traces No. 8. Conrad Bichardson ... ... 03 6 ... 03 0 No. 9. „ „ and North Star... 0 3 6 ... 0 2 0" From these figures it will be seen that there is left in the slags only a very small percentage (a few pennyweights) of the gold and silver, and in one case only traces of gold and silver were found. In order to prove the utility and commercial adaptability of the "process," the company asked Sir Henry Boscoe, President of the British Association for this year, to report upon it. The trial in his presence was on lcwt. of a refractory ore called " New England " from the District of Bavenswood, in Queensland, and the fluxes employed weighed 34p0., and his report is as follows : " The cost of this mixture of fluxes amounts to about 4s. per ton of ore. Before smelting a sample of the ore was carefully collected for assay. The time occupied in smelting the ore was exactly four hours, the mixture being placed in the furnace at 12.40, and the skimming finished and regulus tapped at 4.40. The slag was a good skimming one, and the weight of the regulus was 29£lb. The cost of the operation, exclusive of fluxes, can be taken to be that of the easily-ascertained cost of working a similar furnace in smelting copper ore, which is about 4s. 6d. per ton of ore. Samples (1) of the ore, (2) of the regulus, (3) of the slag, collected by me, were forwarded by me to Messrs. Johnson, Matthey, and Co. for assay. I enclose the report of these gentlemen, which is highly satisfactory. The ton of ore contains 2oz. of gold and 2oz. of silver. The ton of regulus contains^ Boz. 2dwt. of gold and 7oz. sdwt. of silver. The ton of slag contains 7dwt. of gold and sdwt. of silver. It thus appears that in the above operation, which I understand was the first trial of this particularly refractory ore, practically the whole of the precious metals have been withdrawn easily, and at a low cost." The following ig copy of assays referred to in above report: — " Certificate of Assay for Sir Henry E. Boscoe. —We have examined the samples of mineral marked as under, and find the following to be the result per ton of 20cwt. of ore, regulus, and slag :— No. 1. No. 2. No. 3. Ore. Regulus. Slag. Oz. dwt. Oz. dwt. Oz. dwt. Produce of gold 2 9 ... 8 2 ... ° 7 „ Produce of silver ... ... 2 0 ... 7 5 ... 0 5' Further, a sample of 14fb. weight of the very refractory Australian gold-ore, called " Never Never," with the necessary fluxes, weighing 61b., consisting of lime, soda-cake, and fluor-spar, was sent to Dr. Wallace, of the City of Glasgow Analysts' Laboratory, in order that it might be tested on the small scale by this process, and he reported as follows: "I made two experiments, and obtained a good regulus, which separated from the slag readily. I obtained the following quantities

40

n3 a 1-1 S 6 _ & g o-ga br ___ _ > • _ O H A > 6 d .__, o 6 G „ u c3 A 6 .ron jead Jopper mtimony ... jinc 27-00 0-70 0-80 0-70 4-90 7-50 Nil Nil 29-40 Nil Nil 27-30 14-30 3-60 0-20 0-20 4-10 1-40 13-40 3-00 0-30 0-30 4-50 n-50 Traces 15-70 13-70 Traces 13-00 33-20 18-60 0-50 0-80 Traces 6-00 16-30 Traces Nil 15-50 Nil Nil 40-40 22-60 2-00 0-90 •50 6-20 4-50 5-40 Nil Nil 0-10 0-30 0-10 17-20 2-10 0-20 Nil/'' 3-20 Nil Nil Nil* 20-00 Nil Arsenic Manganese ... jime Sulphur mosphorus 3arbonic acid siliceous insoluble matter lold, silver, water, oxygen, and loss Traces 3-10 14-80 Traces 2-50 54-60 Traces 0-80 25-10 Nil 0-40 36-20 Traces 070 2-90 Traces Traces 89-60 I 57-30 1-70 1-20 1-40 1-90 0-80 0-90 100-00 100-00 100-00 100-00 100-00 100-00 100-00 lold (per ton of 20cwt. of ore)... Silver „ „ „ Oz. dwt. 4 12 7 6 Oz. dwt. 0 18 4 3 Oz. dwt, 2 12 2 10 Oz. dwt. 1 18 2 16 Oz. dwt. 3 2 8 18 Oz. dwt. 0 8 0 15 Oz. dwt. 2 12 1 5