This drilling result was part of a broader 658m intersection grading 1.09% copper and 0.86gpt gold.
Harmony revealed that a good portion of this interval went right through the proposed lift 3 area through a diagram in a recent quarterly presentation.
The intersection ended deeper down that this targeted lift 3 area too, indicating there is more deep exploration potential to test in the future.
As for drilling in and around the lift 1 area, Harmony said higher grades extended north outside of its current design.
This lifts the margin per tonne of this block compared to the prefeasibility study estimate, Harmony said.
Unveiled in late August, the Golpu prefeasibility study was for a $US4.8 billion two-lift block cave operation that produces an average of 400,000ozpa gold and 250,000tpa copper in the first 15 years of the 26-year mine life with first production in 2019.
But the PFS estimated a 30 year-plus life and production of 580,000ozpa gold and 300,000tpa copper under the expanded three-lift scenario.
These underground plans are not the full story either, as the associated Wafi copper-gold deposit is within open cut minable depths with a concept study still ongoing.