Stavely Minerals confirms significant new porphyry target at Cayley Lode
Stavely Minerals managing director Chris Cairns says the review provides the company with an “exciting new exploration direction”.
A recent review of data and drill core from the Cayley Lode deposit at Stavely Minerals’ (ASX: SVY) namesake copper-gold project in Victoria has identified a significant new porphyry target.
The review suggests that mineralisation at Cayley Lode is transitioning from ‘high-sulphidation’ to ‘intermediate sulphidation’ high-grade copper-gold in the south-east.
It is believed to be transitioning in character from a distal 250° Celsius to 300°C high-sulphidation assemblage with characteristic copper sulphide minerals enargite and covellite, to a 450°C intermediate-sulphidation assemblage with chalcopyrite, hematite, specularite and magnetite.
Thermal stability
Stavely said the assemblage demonstrated by the last and deepest drill holes at Cayley Lode reflects temperatures of deposition/thermal stability which would be considered proximal to the causative porphyry that has been long targeted by the company.
The transition is also believed to be associated with a significant increase in the relative gold grade, approaching equivalence to copper grades.
This is demonstrated in the intercept of 10.4 metres at 4.34% copper and 3.17 grams per tonne gold and 11g/t silver from 421m, including 4.9m at 6.74% copper, 6.45g/t gold and 19g/t silver from 426m.
New exploration direction
Managing director Chris Cairns said the review provided the company a new exploration direction based on targeted drilling to pursue the Cayley Lode.
“The south-eastern plunge already represented a valid and exciting near-resource exploration target given the increasing width, grade and tenor of the mineralisation in our last few deeper drill holes,” he said.
“We have now recognised that the mineral assemblage in these holes into the Cayley Lode show an increase in temperature of mineral formation which, if it continues, should bring us towards the causative porphyry.”
He said the company was planning to drill a number of wide-spaced diamond holes to “walk the mineralisation down” below the base of existing drilling at approximately 380m depth and test for a continuation of the Cayley Lode to approximately 700m.
“We expect that it is likely the will transition further into porphyry-style copper-gold mineralisation,” he said.