Ore Grade / Tonnage Estimator

Multi-block reserves · weighted grade · cutoff filter

Units & Method

Unit System

Ton Type

Grade Unit

Method (label) All three combine block areas the same simple way here — enter each polygon/triangle as a block. Geostatistical methods (kriging) are out of scope.

Ore Blocks (★ add freely)

Cutoff Grade (optional)

Economic Cutoff Grade Blocks below cutoff are classified waste and excluded from the reserve. Leave blank to include all.

Result

Add your ore blocks with area, thickness, specific gravity and grade to get total tonnage, the tonnage-weighted average grade, metal content and a per-block breakdown — with an optional cutoff grade splitting ore from waste

Tonnage here is volume times specific gravity, and the average grade is tonnage-weighted — each block contributes in proportion to its mass, which is why a large low-grade block pulls the average down more than a small one, and why a simple mean of grades is wrong whenever blocks differ in size. Specific gravity should be lab-measured on your own ore whenever possible: the built-in reference values are broad typical ranges, and in-situ bulk density also differs from solid-rock SG through porosity, moisture and voids. The cutoff comparison shows how the economic threshold reshapes the reserve, but real cutoff decisions also involve mining, processing and price assumptions. This is a basic deterministic estimate for study and preliminary work — resource and reserve reporting for investment purposes must follow recognised codes (JORC, NI 43-101, SAMREC) with geostatistical estimation and a competent person sign-off.