Mineral resource estimation

Mineral resource estimation is used to determine and define the ore tonnage and grade of a geological deposit, from the developed block model.

Depending on the nature of the information and whether the data is hard copy or computerized, the principal steps of computer resource estimation are: An orebody model serves as the geological basis of all resource estimation, an orebody modeling project starts with a critical review of existing drill hole and surface or underground sample data as well as maps and plans with current geological interpretation.

Drill hole and/or sample databases are set up to suit all the quantitative and qualitative information necessary to build a resource model.

Several different mathematical methods can be used to do the estimation depending on the desired degree of precision, quality and quantity of data and of their nature.

The theoretical basis for the method was developed by the French mathematician Georges Matheron based on the Master's thesis of Danie G. Krige, the pioneering plotter of distance-weighted average gold grades at the Witwatersrand reef complex in South Africa.

Advantages Disadvantages The block model is created using geostatistics and the geological data gathered through drilling of the prospective ore zone.

Once the block model has been developed and analyzed, it is used to determine the ore resources and reserves (with project economics considerations) of the mineralized orebody.

A mineral resource can be explained as a concentration or occurrence of diamonds, natural solid inorganic material, or natural solid fossilized organic material including base and precious metals, coal, and industrial minerals in or on the Earth's crust in such form and quantity and of such a grade or quality that it has reasonable prospects for economic extraction.

The estimate is based on limited information and sampling gathered through appropriate techniques from locations such as outcrops, trenches, pits, workings and drill holes.

The estimate is based on detailed and reliable exploration and testing information gathered through appropriate techniques from locations such as outcrops, trenches, pits, workings and drill holes that are spaced closely enough for geological and grade continuity to be reasonably assumed.

The estimate is based on detailed and reliable exploration, sampling and testing information gathered through appropriate techniques from locations such as outcrops, trenches, pits, workings and drill holes that are spaced closely enough to confirm both geological and grade continuity.

When the Bre-X Minerals ltd. scandal was revealed in the spring of 1997, it was one of the largest core salting scams in history and galvanised the development of the NI 43–101 reporting standards.

Bre-X bought the Busang site in March 1993 and in October 1995 announced significant amounts of gold had been discovered, sending its stock price soaring.

[4] Plainly put, the purpose of the National Instrument 43-101 is to ensure that misleading, erroneous or fraudulent information relating to mineral properties is not published and promoted to investors on the stock exchanges overseen by the Canadian Securities Authority.

"[6] The promulgation of a codified reporting scheme makes it more difficult for fraud to occur and reassures investors that the projects have been assessed in a scientific and professional manner.

20 points and their Voronoi cells (larger version below ).
Inverse distance interpolation for different power parameters p , from scattered points on the surface .
Example of one-dimensional data interpolation by Kriging, with confidence intervals. Squares indicate the location of the data. The Kriging interpolation, shown in red, runs along the means of the normally distributed confidence intervals shown in gray. The dashed curve shows a spline that while smooth nevertheless departs significantly from the expected intermediate values given by those means.