Mineralized Intervals

Overview

Mineralized intervals are a core preparation step before building geological or estimation models.

They help transform raw drillhole data into interpretable mining intervals that can be used for:

• compositing
• reporting and plots
• surface/section generation
• downstream modeling workflows

Mineralized intervals are always calculated, they dont hold their own values. This mean for example, if you would export an interval set and reimport it at some point, if your assays change in between, the interval values will change as well. If you would reimport assays and have change in your assays values, your intervals values will also change. There is a “recalculate intervals” tools in the ribbon menu to manually recalculate intervals if you want to update them after a change in your assays.

How Intervals Are Stored

Intervals are stored in sets.

• A new project starts with a Default set.
• You can create as many sets as needed (by cutoff, domain, scenario, etc.).
• Only one interval set is active at a time.
• The active set is the one used for display and by several downstream tools.

Open the Intervals list from the ribbon or with shortcut I.

Interval Structure

A mineralized interval is tied to one drillhole and includes:

• hole name
• from depth
• to depth
• tag/zone
• computed variables (for example grades)

Create Interval Sets

From the Intervals dialog list, use Create:

• By Assays: one interval per assay interval
• By Holes: one interval spanning each hole
• By Optimization…: cutoff-based optimized intervals
• By Geology…: intervals from lithology/mineralization/alteration grouping
• From Composites…: create intervals from a composite set
• Missing From Envelopes…: build intervals for holes missing coverage in selected envelopes

Optimization-Based Intervals

Create > By Optimization… is commonly used to generate economic interval candidates from assays.

The optimization groups adjacent assay segments according to cutoff and constraint rules, then applies post-processing filters.

Once you have selected your properties and press ok, the creation algorithm works mainly this way:

• Regroups adjacent assays that exceed the specified cut-off grade within intervals containing positive values.

• Regroup the spaces between intervals of positive values, in intervals of negative values.

• It is possible to join two intervals positive values considering the dilution of the negative range (if exceeding the cut-off value), uniting the tree intervals into a single interval.

• Once completed, reject all intervals not meeting the minimum size specified mining pillar.

General settings

• Variable
  Numeric variable used for optimization (for example Au, Cu, etc.).

• Intervals Set Name
  Name of the output interval set.

• Cutoff Grade
  Minimum grade target used to separate potentially economic vs waste intervals.

• Multi Cutoff Grade
  Creates several sets in one run, each with a different cutoff.

• Max Cutoff Grade / Step Cutoff Grade
  Upper bound and increment used when multi-cutoff is enabled.

• Mining Pillars
  Minimum separation constraint between intervals along hole trace. 0 means no pillar constraint.

• Minimal Length
  Minimum accepted interval length.

Algorithm control

• Fit to Assays
  Forces interval boundaries to assay boundaries. If disabled, interval limits can cut across assays.

• Maximum Size of Good
  Limits how large positive/good zones can be when considering merges through waste.

• Maximum Size of Waste
  Limits waste gap size allowed between two good zones for merging.

Post processing

• Chop to Mining Pillars
  Trims large intervals to respect pillar constraints.

• Erase Under Mining Pillars
  Removes intervals that still cannot satisfy pillar requirements.

• Erase Under Minimal Length
  Removes intervals shorter than minimum length.

• Erase Under Minimal Metal
  Removes intervals below a minimum metal threshold (grade × length). 0 disables this rule.

Calculation settings

• Dilution
  Grade used for unassayed waste portions during optimization calculations.

• Use Assays Capping
  Applies temporary assay capping for optimization behavior control.

• Assays Capping
  Capping value used when capping is enabled.

Practical interpretation

In simplified terms, optimization typically:

1. Builds positive and waste candidate segments from assays.
2. Merges or separates intervals using cutoff and waste/good-size limits.
3. Applies pillar/length/metal post-filters.
4. Outputs one or multiple interval sets depending on cutoff mode.

Extract and Build New Sets

Use Extract:

• From Tag…: create new set(s) from interval tags
• From Envelope…: extract intervals inside envelope(s)

Envelope extraction includes options such as:

• exact vs center-based extraction
• optional precision mode
• tag by envelope
• piercing checks
• optional snap-to-assays constraints

Set Operations

Use Operation to combine or transform interval sets:

• Union
• Intersection
• Substraction
• Negation
• Addition
• Merge
• Use Formula…

Notes:

• Multi-set union/addition is supported.
• Merge can overwrite the destination set.
• Use Formula when you want a complex multi bool operation between sets (for example (A AND B) OR (C AND NOT D)).

Tagging and Snapping Tools

Additional operations:

• Tag By Dictionary…: tag intervals from selected table dictionary/tag values
• Tag By Envelope…: apply tags based on envelope intersection
• Snap To Assays: create a snapped version of interval set using max from/to shift distances

Generate Geometry From Intervals

From Generate, interval sets can be converted into quick interpretation geometry.

Surface Envelope

Creates a surface from interval positions (commonly from interval tops or bottoms, depending on settings).

Typical usage:

• build a rapid surface from one interval set using top or bottom intervals
• optionally focus on specific tagged intervals
• use result for visual interpretation, comparisons, or as an input to other workflows

Faces Envelope

Creates a face-based envelope from interval geometry.

Typical usage:

• fast implicit-style volume approximation from interval clouds
• quick shape preview before more advanced modeling

This is useful for exploratory iterations when you need a rapid geometric boundary.

Section

Creates a best-fit section from selected interval geometry.

Behavior:

• section orientation is computed from interval spatial distribution
• section view is adjusted to fit interval extents
• output section is added to the section set for immediate review

Typical usage:

• quickly obtain the most informative cross-section orientation for a zone
• compare orientation across different interval scenarios

These generation tools are intended for fast interpretation support between interval construction and full modeling.

Validate and Log

From Report:

• Validate… checks selected sets for key issues
• View Log… shows interval-set creation/operation history

Validation reports include checks such as:

• overlaps
• orphan intervals (hole references not matching active drillhole data)

When issues are found, helper sets can be generated (for example overlap/not-orphan review sets).

Import and Export

From File:

• Import interval sets from supported formats
• Export one or multiple sets
• View simply open your default csv viewer/editor with the selected set

Common formats is CSV

Dilution Reminder

Interval grade results depend on dilution settings.

If gap dilution/default filling is enabled in data constraints, gaps between assays can contribute default values to interval calculations. Keep this setting consistent across scenarios when comparing sets.

Practical Tips

• Build and compare multiple sets (for example different cutoffs) instead of overwriting one set.
• Keep clear naming and folders for scenario tracking.
• Run Validate before generating composites and model inputs.
• Use Snap To Assays when strict assay-boundary alignment is required.