Locating the assay value of a mapped reserve is an important part of developing a gold mining project. However, the market value of a mapped reserve is the project’s extraction value, not the assay value. The following are the definitions used as baseline for assay and value discussions:
Standard assays are used to establish how much free precious metals are in a mapped reserve (recoverable by a standard processing operation). Standard assays use little to no pretreatments before assaying a sample. Therefore, the standard assay value is almost always lower than the values reported by sophisticated assays.
Sophisticated assays are used to establish how much free, complex, and micron precious metals are in a mapped reserve. Sophisticated assays use a number of refined pretreatments before assaying a sample. Therefore, sophisticated assays show the true assay value of an ore body, which is generally higher than the values reported by standard assays.
The assay value is used in a project evaluation process to establish how much wealth in the form of precious metals is located within a project’s mapped reserves.
The extraction value is the value of precious metals that can be recovered from a mapped reserve with a pilot plant using affordable mechanical processes that are environmentally friendly. Before investing in building a processing plant, conducting enough laboratory and pilot plant extraction studies is necessary in order to locate the extraction value of a mapped reserve.
