Tertiary Minerals plc has intersected “thick intervals containing anomalous copper values”, possibly in the halo of a porphyry deposit, at its Brunton Pass copper-gold project in central Nevada, USA.
THESIS
The first pass phase I drilling programme, started in November 2024, comprised four reverse circulation percussion drill holes for a total 890m.
The company said that the copper values were associated with fresh and oxidised pyrite and trace chalcopyrite.
Results showed “cumulative” drill thicknesses up to 210m grading 170ppm copper with up to 0.19% copper over 1.53m.
The anomalous copper values extend to at least 212m vertical depth, 630m east-west and 560m north-south.
Tertiary added that surface mercury and arsenic indicator anomalies persisted at depth which could undergo future deeper diamond drilling.
Plans include petrographic and additional geochemical analysis to aid future drill targeting.
“Only the peripheral parts of the IP anomaly have been intersected at depth so far and the stronger parts of the anomaly remain untested,” said executive chairman Patrick Cheetham.
“Our working thesis is that we may have drilled within the halo of a porphyry copper deposit and that deeper drilling is justified.”