Define Narrow Ore Settings

The Narrow Ore Advanced setting is designed to help MSO better recognize and recover narrow but valuable sections of ore that might otherwise be excluded due to their high internal waste or marginal width.

By adjusting how MSO interprets waste in specific areas of the stope shape, this feature improves recovery for orebodies such as thin veins or stringer zones.

When enabled, MSO applies a waste substitution rule to selected areas of the stope (e.g., near side, footwall, centre), allowing limited waste material to be treated as ore during the optimization process.

Activity steps

Define an MSO scenario, block model, orientation, framework and shapes.
Display the Advanced screen.
Expand the Narrow Ore command group.
Check Use Narrow Ore. When active, MSO applies the configured waste threshold and substitution rules.
Defines which part of the stope is eligible for narrow ore substitution:
- Near
- Far
- Footwall
- Hangingwall
- Centre
Define the Waste Threshold. This is the percentage of waste that must be exceeded for MSO to consider substitution (set to 0 for full effect).
Define the Waste Background Value. This is the value MSO uses to substitute waste blocks in the selected position (for example, 0.001 to simulate low-grade material).
Save your settings.

Narrow Ore Example

Consider the following example:

You're working with a narrow vein deposit where some slices have thin, high-grade ore zones surrounded by a small amount of waste on the footwall side.

You can enable Use Narrow Ore, set Position = Footwall,

Set Waste Threshold = 0, and Waste Background Value = 0.001.

This tells MSO to treat any small amount of waste on the footwall side as low-grade ore, allowing the algorithm to recover narrow veins that would otherwise be excluded.