In any drilling campaign, the hardest decision will be when to stop drilling. Some of the situations which may warrant this decision are as follows (Gandhi & Sarkar, 2016):
- no mineralization was encountered;
- mineral resource intersection was not up to desired grade and width;
- limited continuity of mineralization of economic resource grade, size might be small for the investigating agency. Type of prospect not interested by one party might be of interest to some other party;
- delineation and establishment of an orebody of economic grade and size;
- exhausion of budgeted funds.
Reexamining a prospect (recycling) that a previous party has discarded for various reasons is a tempting proposition, but the buyer must be satisfied that they can be more meaningful than the earlier exploration company. This success might result from different exploration models or improved exploration techniques. There were instances of good successes.
Reference
Gandhi, S. M., & Sarkar, B. C. (2016). Chapter 8—Drilling. In S. M. Gandhi & B. C. Sarkar (Eds.), Essentials of Mineral Exploration and Evaluation (pp. 199–234). Elsevier. https://doi.org/10.1016/B978-0-12-805329-4.00015-6
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