Gold Prospecting Ground Samples
It is advisable to avoid sampling the stratum of superficial humus: the optimal depth varies generally between 15 and 40 cm in depth. Sampling at the base of the herbaceous roots can give you a good and very real indication of the optimal depth. Therefore make sure to avoid the sampling on very developed grounds or in areas that are clearly allochtonous (such as ancient terraces, dunes, etc.). In these cases it is convenient to take into account the sampling by drilling through this covering.
Amount that should be sampled
The amount that should be sampled varies anywhere from 200 to 500 grams, according to the proportions of the fine sediments that are included. This amount allows, after the drying and sifting has been done, obtaining of a sample with a minimum weight of 60 grams. A minimum amount of 40 grams is enough to carry out the current analysis (at least 25 grams in the case of analysis of gold) and 20 grams that will be conserved as a witness. The sample fields will be placed in a covering (18 x 26 cm) or in plastic cups. Note: keep in mind that in a strategic prospection 10 to15 samples per day represent around 4 to 7 kilograms that need to be transported.
Numbering of samples and field booklet
This is a very important part because if mistakes are made or there are samples that have been numbered two times, they can turn into something that cannot be used for the work. The advisable method is a sequential numbering with the field booklet made up by previously numbered files and avoid in this way mistakes. This file also allows the processing of data. In some cases it is advisable to mark the samples on the topographical map by using a square mesh of 1 cm on the side numbering the samples from left to right, and up to down. This method makes easier finding on the map without having to calculate the geographical coordinates.