Project

Economic evaluation

The valorization model it’s useful to quantify the technical and economic variables of each prospect based on its main features. This model considers a shovel and truck operation.

When the prospects were evaluated they were divided into different categories, the prospects with higher potential and that were visited during the field trips were matched up together into one category called prospects of interest. On the other hand, the prospects that weren’t visited or not found but their economic variables turned out to be attractive, formed another category called potential prospects. Finally, the prospects with no economic value or without enough oz. troy of gold to be evaluated with this model were grouped as deposits of little interest.

Field Trips

The main objectives of the field visits were to corroborate the information obtained in the previous bibliographic review, also to complete the consolidated files with information that wasn’t found during the review. During these trips, approximately 80% of the wastes that were included in the List of Alluvial Gold Mining Resources in Chile were visited, and with these observations, much more complete consolidated records were established.

Creation of Consolidated Sheets

Based on the 255 initial files, the process of consolidating files began, gathering information from several initial files in only one per prospect. In addition, with the purpose of characterizing minimally one prospect from the point of view of its exploitation, the consolidated file attempted to complete the most relevant fields for a prospect (Business Potential, Technical Feasibility, other like Exploitation Feasibility and Business Impact), The same ones that were used in the prioritization process.

Finally, from the previous process, 87 consolidated files were created, which after a subsequent critical review, were reduced to only 75, which compose the List of Gold Mining Alluvial Resources in Chile.

Hierarchical Model

Based on the information coming from the consolidated files, which were obtained from the previous bibliographic review, prospect that have more favorable characteristics to be exploited are determined. For this purpose, a hierarchical model is used, which allows us to build up a ranking of the prospects by their higher or smaller potential of exploitation, based on the relative steadiness of each of the relevant variables that were compiled, which is determined from a survey of experts by using a methodology called "Analytical Hierarchy Process" (AHP).

Creation of Technical Sheets

At the same time of the bibliographical revision, technical files were created based on reports that contained relevant information. From the process described above, only 93 references of Sernageomin and 17 of Sonami could be found, with a total of 255 initial files (232 and 23, respectively)

Literature review

The literature review was based on the information available in the libraries of Sonami and Sernageomin. Using different searching criteria relative to gold placers a database was built with all potential references that could contain relevant information, 438 references were reviewed in the Sernageomin library, and another 113 in Sonami, discarding 15 references from the second for being present in the first review.