Arrangements can be made for independent ground and airborne geophysical surveying, geochemical sampling and drilling where necessary. Such undertakings are often expensive and time consuming but are occasionally necessary for independent audit of larger reserves. In contrast, the typical resource evaluation project does not involve ground work or re-measurement of archived data but relies on literature assessment and interview. Basic evaluation comprises of three broad aspects.
1. Summary and description of regional geology involving the claim area and relevant adjoining areas. The purpose of this exercise is to assess the likely physical extent of the resource and the likelihood of additional examples of the target ore being found elsewhere within the claim boundaries. This aspect typically involves academic literature review, and relies heavily on the assessment of geological survey maps and reports and publicly-filed company documents.
2. Geological description of the resource or reserve. The purpose is to establish the size and nature of the resource within the regional geological context and with a view to making an independent statement to accompany the claim holder’s assessment. This aspect is based most heavily on company reports and in the cases where the resource is known historically and is of academic / strategic interest, of academic and survey publications. Assessment is necessarily often constrained by the facts as presented by the claim holder but usually it is possible to side-step corporate selective interpretation of the facts.
3. Economic evaluation. The purpose is to provide an independent assessment of the likely average grade, lifetime and value of the reserve. Sources used are resource data and likely infrastructure and production costs. This aspect of the project typically utilises bulk sampling and drill core and geophysical information typically contained in company reports and married to data available for comparable working mines elsewhere. Once grade and mineable reserve size are reasonably established the application of data from comparable mines allows an economic evaluation which is significantly independent of claim holder’s assessment.Burden of Work
The most basic research-based evaluation would typically engage Trigon in approximately 14 personnel days of work excluding site and client visits where required. However the company and its consultants are available to undertake more detailed projects including survey-based projects depending on the size and significance of the resource and the clients’ needs.