CHELMSFORD.

Auckland Star, Volume XXXI, Issue 63, 15 March 1900, Page 7

CHELMSFORD.

Very satisfactory results have been obtained from two parcels of ore from the Chelmsford mine, Upper Tairua, which were treated at the Thames School of Mines. Parcel X. consisted °f splintery quartz, with iron oxide. It was dry crushed, and gave an assay value per ton of £13 6/7, there being3oz 3dwt of gold and 7oz 6dwt sgrs of silver per ton. Five hundred pounds of a r y crushed ore treated by pan •amalgamation yielded loz lldwt 6grs °f bullion, worth £ 1 12/ per oz. This, is equivalent to a saving of £11 4/ per ton, and shows a saving of 85 per cent, of gold and 57 per cent, of silver, a total of 84 per cent, of the assay value of the ore. 14001b of the drycrushed ore was subjected to cyanide treatment, when 92 per cent, gold, 81 per cent, silver, and 91 per cent, of value of the ore (equivalent to £13 3/8 per ton), was extracted. The pre- ' sence of a considerable amount of iron oxide made the percolation slightly ■troublesome in this test, but, on a ' working scale, with similar ore, a still higher extractipn would be possible.

Parcel 0. consisted of splintery quartz, and contained red oxide of iron seams. It was dryvcrushed and assayed. The assay result was: Gold, loz 7dwt 17gr per ton; silver, 2oz Odwt Bgr per ton. Total value per ton, £5 14/10. 5601b were pan amalgamated for a return of 14£dwt melted bullion, worth £1 14/8 per oz, which is equivalent to a saving of £5 0/7 per ton, and a percentage saving- of S7 per cent, gold, 81 per cent silver, and 87 per cent of value of the ore. 15401b were tested by cyanide ! process, when 93 per cent, gold, 87 per : cent, silver, and 93 per cent, of value of ore was extracted, equivalent to £5 ,7/S per ton. For both parcels the con- • sumption of cyanide was small, and ;the cost of cyanide treatment of such : ores would be low. The actual recovery of bullion from the cyanide treatment of the two parcels was Soz lndwt melted bullion, worth £1 4/2 per oz. Thus bullion worth £10 11/5 was Obtained from 14001b Parcel X. and 1500 parcel 0. —both being cleaned up together—and shows a percentage actual recovery of S6 per cent, gold, 78 per cent, silver, and 84 per cent, of the value of the ore from the two parcels. The ore is easily crushed by stamps, and affords no difficulties in treatment.