Sampling Technique

Each sample will be made up of two samplings done in two points, various meters of distance from one to the other and outstanding in their concentration of heavy minerals where the gravel is very potent and that have the least amount of mud as possible. The gavel is sampled at a variable depth between 10 to 40 cm if it is not possible to directly reach the bed rock and a sifter with 5mm is set up. Two pans are filled and the amount should be known so as to be able to determine in the future, the possible tenors; either way it should contain at least five liters of sand. The waste that is left on the top of the sifter needs to be visually checked in order to see if there is any presence of bigger mineralized elements; this will also in the same way be done for the smaller streams that will be washed inside of the pan and will need to be take out by hand. The sand that is left inside, that has been well cleaned of the fractions of clayish silt will need to be washed with circular movements so that the external parts come out more until obtaining a concentrate of heavier minerals with a good amount of minerals that have a medium density. The concentrates of the two pans will be put together in one cup or bucket for sampling and with respective label.

Organization and materials
The following are necessary in a team:

• 1 prospector and team chief
• 1 or 2 samples and workers
• 1 shovel
• 1 axe
• 1 5mm sifter
• 2 stainless steel buckets or pans of 8 litres
• Recipients, covers and labels for samples
• 5 to 6 carriers, in the case of isolated zones and those in tropical jungles
• Depending on the situation, 1 hunter

As far as the pan in concerned, it is advisable to use the conic type of pan which has a hole on the wall and that serves as a trap for the heavier minerals. The usefulness of a pan is variable depending on the area the prospector is in. in areas where there is a good amount of rods, it is possible to get to around 10 to 12 samples per work shift of 8 hours of work. In tropical areas, keeping in mind the difficulty of penetration, the outcome is reduced down to 2 to 4 samples for every 8 to 10 linear kilometers on the map, or must have a density of 1 to 2 samples/km2, in our words an alluvial sample of every two geochemical samples in campaigns of mixed prospecting, as are generally done.