What an in-house 3D deposit estimate can and cannot do

The drill logs are in, and the director asks the obvious question: what do we have? Until now the honest answer has often been “wait”. The data goes off to expensive desktop software and a consultant, and the next drilling decision has to be made before the picture comes back.

An in-house model answers that frustration, and it creates a risk of its own. A tonnage on a screen looks very authoritative. Once it reaches a board slide or a conversation with an investor, people tend to forget how it was made.

What an indicative estimate is for

An indicative estimate serves internal decisions. Where should the next hole go? Is this target worth another campaign? How much does the tonnage depend on the cut-off we assume?

It does not serve public disclosure. A resource statement under JORC or NI 43-101 requires a qualified person who takes responsibility for the data, the method and the classification. FlexiMining labels its output accordingly: the 3D module gives an indicative, in-house estimate to guide exploration decisions. It is not a certified resource statement, and a qualified person should review the figures before any external or financial use.

Do you still need specialist desktop software? Not for day-to-day exploration modelling, because the platform builds the model, the tonnage and the contained metal itself, with no separate desktop licence. For an official statement, you still need that qualified person to sign it off.

How the model is built

Your drilling data comes first: collars, surveys, rock logs and assays for every hole, attached to the permit and editable from the phone. A whole campaign can come in from one Excel workbook and go back out the same way. Inclined holes follow their true path underground, so each sample sits where it was actually taken.

Grades are then estimated across the deposit with methods geologists already use, as an indicative estimate in 20 m blocks. The model stays inside your permit boundary and the depth you have actually drilled, and you can turn and slice it on the phone or on the web.

How to read the numbers

Set a cut-off grade and tonnage, average grade and contained metal update straight away. Moving that slider is one of the quickest ways to learn how sensitive a target really is. A tonnage that collapses at a slightly higher cut-off tells you something important about the deposit.

Colour by confidence before you read the totals. This view separates blocks on a drill hole, blocks between holes and blocks beyond the holes. A large tonnage that rests mostly on blocks beyond the holes says more about how sparsely you have drilled than about the size of the deposit.

Watch two other controls as well. A wider model extent, from around the holes to joining them to the whole permit, can produce a bigger number with no new data behind it. Vertical stretch makes thin structures easier to see, and it also distorts their geometry, so check the true shape before drawing conclusions.

Each model is saved as a version you can come back to and compare with another, which helps when you want to see what a new round of holes really changed.

Where it has to stop

A model is only as reliable as the surveys and assays behind it, so errors in the drill data carry straight through to the figures. Keep the word “indicative” attached to the numbers when they leave the building. If a figure is heading for a report, a financing or a filing, it goes to a qualified person first.