A manto is a tabular or sheet-like form of carbonate replacement mineralisation, often resulting from replacement along layers of limestone with metal sulphides.
Highlight true-thickness manto grades assayed by Inca include:
• 2.3 metres at 13.08% zinc, 254.4 g/t silver, 9.82% lead;
• 1.55 metres at 8.07% zinc, 161.9 g/t silver, 4.72% lead; and
• 1.57 metres at 7.02% zinc, 181.4 g/t silver, 3.63% lead.
The manto is exposed in a shallow mine working northwest of Mine 4548
Inca managing director Ross Brown said: “Wherever the manto is identified, it is proven to be well mineralised with true thicknesses and grades of real economic interest.”
Importantly, the manto bears towards the Rastrillo Deposit, where there is a concentration of well mineralised veins, breccias, stockworks and mantos.
As well as the Callancocha Structure, manto mineralisation such as this, may prove to connect zones of mineralisation such as Rastrillo and Rastrillo North at Humaspunco.
Brown added: “It is this connectivity that adds to the bulk tonnage potential of this exciting prospect area”.
Channel sample with a grade of 14.12% zinc, 207 g/t silver and 8.22% lead
Inca has also recognised the manto exposed in Mine 4548 in drill holes with grades of 4.97% zinc, 119.6 g/t silver, and 3.06% lead over 1.3 metres. Moreover, this manto is open ended in most directions.