Step-out drilling is a geological and mining exploration technique used to test the outer boundaries, depth, or strike extensions of a known mineral deposit or ore body to see if the deposit is larger than previously mapped.
- Risk vs. Reward: It carries a higher risk of hitting unmineralised rock compared to infill drilling, but a successful step-out can dramatically increase a project’s size and economic value.
- Purpose: It goes beyond the current known resource boundaries or pit shells to find new ore and increase the total estimated mineral reserve.
- Placement: Holes are drilled at set intervals (steps) away from existing positive drill intercepts or known mineralized zones—either laterally along a strike/trend or deeper down-dip/down-plunge.
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