Loaming prospecting is a preliminary prospecting technique whose main objective is to get any signs of gold. In order to do this, the process consists in making trenches or some small perforations in the potential area. The place is washed from the base and slopes of the ranges until gold or any gold bearing mineral is shown. Then, the gold prospector starts to follow the gold up the hill until the rich deposits and after a patient prospecting activity the gold vein is reached. Basically, at the moment that the gold prospector arrives to the right place, a trench is made.
It is common to prospect a long a steep scrubby mountain side selecting the starting point, identifying it and taking samples. When a potential place is found, the prospector has to way back to the spots where the samples were taken and continue a hill up search and trace the gold to its source or vein. It is important to indicate that sometimes there is no indication of a vein due to bushes or debris cover its location. For this reason, the loaming activity needs attention. By loaming it is possible to identify some characteristics of the gold deposits such as the cleavage of quartz, which looks free, sharp and well defined. Obviously, this characteristic is important in high gold grade deposits. In this case, the presence of pyrite is important and also a clayey or gouge formations, which flank the vein in its gold bearing portions.
When the results are positive, the veins must be examined carefully. If the quartz is hard, it stands up, if soft, it leaves a streak like depression. During prospecting, it is important to wash out some of the decaying rocks. When a trace of gold is found in quartz formations, it is possible to find a gold vein very close and the trenches must be made. Typically, gold may be present near one wall of a vein and rarely all through the stone. Quartz may be detected in branches with non-valuable minerals.
When is suspected that a gold placer does not show good qualities or potential. It is important to observe and examine carefully cross cuts because more gold may be located in leader veins, which were overlooked during the preliminary exploration. Other interesting point is the lower part of a placer where the pebbles and sand are together in coarse conglomerates with presence of iron oxide. Placers are richer in some points and no necessarily in the veins from which gold was derived. Shallow placers are formed due to the wearing and abrasion of quartz veins and the rich parts are not above these veins and the gold prospector must be able to examine the zone and detect the course of the vein and the mineralization.