Before going into an analysis of the ore composition, two other major factors will affect the result. These are the accuracy of the assay and the effectiveness of the mill for the gold recovery.

This assay system of ounces per ton sounds simple enough, but the use of the metric system and the additional measuring terms of “grams per ton” and “parts per million” (ppm) has created some misunderstanding of ore value.

The first and most important thing of the sampling process is to try to be as unbiased as possible. There is a natural tendency to select rock that looks the best—even unconsciously.

Rivers are not just random and accidental; streams and other drainages are what they are because of the forces of erosion acting on the bedrock.