Reentry Quantity
Reentry Quantity is the minimum tonnage that must be mined before the tool is allowed to switch back to a previously restricted grade category.
What it does
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Prevents the schedule from “bouncing” between high-grade and low-grade stopes.
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Forces the optimiser to commit to mining a reasonable chunk of material before reconsidering options that were excluded due to quality constraints.
Why it exists
Without it, the tool could:
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Mine 1t of 2%
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Then 1t of 10%
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Then back to 1t of 2%
… And keep oscillating forever.
Specification of a Reentry Quantity creates stability and inventory depth
Effect of size
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Low value ® frequent switching.
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High value ® longer runs in one stope before switching.