THE Yelta copper mine is situated less than one mile north of the well-known Moonta mine, in South Australia-in fact, the Yelta boundary abuts on to that of the Moonta. The property was purchased and taken over by a French company-the Paramatta Copper Mines Limited-early in May, 1903, and worked in conjunction with their previously acquired mine, the Paramatta, which lies about one mile further north. The chief lode on the Yelta, and the only one at present being actively worked, appears to be a continuation of one of the Moonta lodes, and the country rock is also the same-viz., felsite porphyry. The vein-stuff, however, differs greatly in its main characteristic from the Moonta, as although the ore itself-ordinary copper pyrites, with occasionally a little bornite-is similar, the Yelta lode contains in addition a large proportion of hematite, the matrix proper consisting chiefly of quartz and a silicious felspathic material very similar to the encasing country rock. The copper pyrites and the hematite are intimately associated, and with the silica present the mixture offered a very fair smelting proposition, and it was largely in consequence of the recognition of this point that the property was secured.