Field report Aug 24 2010
In response to shareholder requests for more detailed reporting on mining operations and equipment purchases I would like to address these issues.
Mining operations;
SGCP is currently involved in placer mining in Sierra Leone and as such hold mining concessions in Zimmi, Bo and Pampana. Currently we have mining licenses on properties in the Zimmi district on the Mano and Mowa River and Bo district on the Sewa River. In order to clarify for those investors unfamiliar with placer mining process I would like to explain this further. First of all, we are using dredges that are located on rivers. The dredges are used for the removal of overburden which is any type of dirt or sand above gravel layers of interest or false-bottom (endured clay). If the gravel layers of interest are above and in the bedrock, you basically vacuum up the gravel. If you run into a false-bottom where the most interesting gravel layers are located, the dredge operator must use a cutter head to allow deeper access to this gravel and then vacuum up the gravel. Depth and quality of gravel varies from location to location and testing is done to determine these factors.
Placer deposits have been exploited by man since early historic time and have remained an important source of gold on the world market into the 21st Century.
Placer deposits have yielded over 60% of the world's gold production.
Dredges:
Essentially our 50 ton per hour dredge is a vacuum and classifier. It’s the primary means of recovery and separation of gold and gems in an underwater operation. These units are mobile and can be moved on the river as necessary.
It works by pumping water to create a vacuum allowing material to be sucked off the river bottom. Once it is pulled to the surface it is then slowed down and run across a sluice box. By doing this, it creates a high and low pressure area. Gold and gems by their specific gravity weight will naturally settle to the low pressure areas because they are heavier than the rest of the river material (sand & gravel). The dredge is rated on how many tons of material it can process per hour at full throttle. A dredge operator will adjust the flow to provide the best recovery per the amount of material processed, In other words, the finer the gold and gems the less material it can process without loss.
Our 100 ton per hour unit is a larger piece of equipment using gravel pumps hooked to a wash plant. The wash plant we have in operation is a trommel and sluice box combination. The gravel pump sucks up the river bottom and sends it to the trommel.
A trommel is a washing machine for gravels and clay. It rotates and washes while breaking up the clumps of clay that contain the gold and gems. The trommel has a screen on it that allows smaller material to fall through and move on to the sluice box for concentration. The larger material that won't pass through the screen will be discarded out the end of the trommel to either be put back through or discarded as tailings
This set up is best served in a stationary location with a large amount of clay and material to be processed.
Per our field report dated July 26, 2010 we have on location in Sierra Leone three 50 ton per hour and one 100 ton per hour units.
Our mobile Wash Plants will be deployed to locations as upcoming mining season dictates and work separately from our dredges.
We hope that this brief, detailed explanation of the mining and dredge process currently incorporated by SGCP has been useful to the shareholders and you have gained a better understanding of how the company is utilizing the natural resources of Sierra Leone as well as the equipment purchased and built for the extraction of said resources.
John Semachko Jr
President
Sierra Gold Corp.
