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rich and free-milling it is easier to save a higher percentage of the bullion than with free-milling poor ores. Mr. Luhrs estimated that he had obtained from 450z. to 50oz. more than would have been recovered by the ordinary battery process. "No. 9. —This was a parcel of hard bluish-quartz from the new find at the Great Barrier Island. It contained a little free gold and silver, principally in the form of the free-milling chloride. Traces of ruby silver, pyrargyrite, also showed throughout the stone. The ore weighed 2251b. It was pulverized dry, sampled and assayed, showing the following value per ton :— Oz. dwt. gr. "Bullion ... ... ... ... ... ... ... 47 19 14 Gold 7 16 12 Silver ... ... 40 3 2 Value, £37 6s. lOd. " It was raw hot pan-amalgamated with chemicals, and yielded 3oz. of bullion, 236-8 fine in gold and 737-7 fine in silver, equal to a value of 19s. 2d. per ounce, representing a saving of 91 per cent, of the gold and 55 per cent, of the silver, or 85 per cent, of the assay-value. " No. 10. —This was a parcel of 1061b. of ore from the Silver Queen Mine, at Maratoto. It was crushed dry, and showed the following assay-value per ton: — Oz. dwt. gr. "Bullion ... ... ... ... ... 276 0 0 Gold ... ... ... ... 5 0 20 Silver ... ... ... ... ... ... ... 270 19 4 Value, £60 16s. 4d. " Tests in the laboratory had shown that the silver existed as a telluride, which was not freemilling ; however, at the request of the owner, Mr. W. Eddowes, the test was continued. The pulp was subjected to pan-amalgamation with chemicals, and yielded 2oz. 6dwt. of melted bullion, 097-8 fine in gold, and 846-6 fine in silver, representing a saving of 94-2 per cent, of the gold and 15-4 per cent, of the silver, or 40-8 per cent, of the assay-value. "It is probable that the silver saved was that alloyed with the gold. Cyanide of potassium was found not to attract the bullion. A number of tests in the laboratory with this interesting ore showed that from 40 to 50 per cent, of its value was volatilised at a bright-red heat in less than two hours. These results showed it would be useless to attempt to chloridize roast the ore, without incurring a great loss of bullion. "No. 11. —This was a parcel of 701b. of brown-colouredqnartzfrom a new find between Marototo and Waitekauri. It was crushed dry, and showed an assay value per ton of:— Oz. dwt. gr. "Bullion ... ... ... ... ... ... ... 32 10 0 Gold ... ... ... ... ... ... ... 2 18 6 Silver ... ... ... ... 29 11 18 Value, £16 Is. Bd. "It was then raw pan-amalgamated with chemicals, and yielded 14dwts. 16gr. of melted bullion, 105-6 fine in gold, and 874-8 fine in silver, valued at lis. per ounce, representing a saving of 88 per cent, of the gold, and 85 per cent, of the silver, or 83-2 per cent, of the assay-value of the ore. "No. 12.— This was a parcel of 2,0651b. of moderately-hard yellowish-brown quartz, forwarded by Mr. W. H. Skeen from Waitekauri. It contained free gold and silver in the form of argentite. The ore was dried, dry crushed, sampled, and subsequently assayed, showing an assay-value per ton of: — Oz. dwt. gr. "Bullion ... ... ... ... ... ... ... 14 2 0 Gold 3 0 12 Silver 11 1 12 Value, £13 15s. 3d. " The dry pulp was then treated by raw hot pan-amalgamation with chemicals, and yielded 9oz. 16dwt. of melted bullion, 230-4 fine in gold, and 749-6 fine in silver, representing 81-6 per cent, of the gold, and 72-5 per cent, of the silver, or 80-5 per cent, of the original value of the ore. "No. 13. —This was a parcel of hard greyish-blue quartz, often flinty and brecciated. It contained only a trace of gold, and silver in the form of the dark-blue sub-sulphide, argentite, and ruby silver or pyrargyrite, the latter in the greater proportion. " The dry pulp, weighing 2,9401b, was raw hot pan-amalgamated with chemicals, and yielded 7oz. of melted bullion, representing a saving of 97-1 per cent, of the gold and 26-1 per cent, of the silver, the original assay-value per ton of the dry sampled pulp being : — Oz. dwt. gr. "Bullion 21 16 1 Gold 0 3 1 Silver 21 13 0 Value, £3 17s. 4—C. 3.