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Eastmain is a Canadian exploration company committed to adding value through the discovery of base and precious mineral deposits in Canada. Our strategy has been to acquire and evaluate properties with high discovery potential, both within well-established mining camps and in unexplored frontiers.
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Canada is a world leader in production of base and precious metals, especially gold, zinc and nickel. Many of the giant ore deposits in the world occur within "greenstone belts", which are ancient slivers of volcanic and sedimentary rocks. Eastmain is actively exploring for base metal (zinc, lead and copper) massive sulphide deposits within volcanic rocks. These ores are often referred to as VMS deposits (Volcanic Massive Sulphide). Our Railroad project is a good example of a VMS property with excellent discovery potential for base metals.
The first step in exploration is to acquire a property with high potential either by staking land which is owned by the crown or by optioning the property. Once the company has acquired a property, the holder is required to perform work in order to maintain its mining rights. The holder must submit technical reports to the government as proof that exploration work has been completed. The potential of any given property is commonly measured by that property's technical similarities to those of giant producing mines. Our basic exploration "toolbox" includes geology, geophysics, geochemistry and diamond drilling.
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 GEOLOGY:
First the geological recipe: Mother nature has formed ore deposits throughout the world with remarkable consistency. Like any good cookbook there are many ore deposit types, similarly we often have our favourite geological recipe! At Eastmain, we have selected properties which match the fingerprint of world-class producing mines. As with icing in a layer cake, ore deposits tend to occur within or along a specific bed of geology. Our initial focus is to evaluate the "favourable beds or horizons" for geological signs of metal deposition.
One parameter we use is rock alteration. As an ore deposit is being formed, a chemical reaction often occurs within the layers of rock containing the potential mine. This alteration may result in both a mineralogical and/or chemical change within the rocks. Generally the alteration zone is much larger in area that the ore deposit itself. Ideally the alteration zone will lead the explorer to the ore deposit.
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GEOPHYSICS:
Base and precious mineral deposits within the Canadian Shield are often found within or associated with metallic sulphide minerals which commonly have strong magnetic and/or electromagnetic properties. With geophysical instruments, we measure the physical parameters of rocks from the air (airborne geophysics) or on the ground in a systematic grid pattern. Our objective is to search for anomalies which may reflect a potential orebody. With advancing technology, we can create two- and three-dimensional coloured geophysical maps in our quest for the next Voisey's Bay or Hemlo deposit. These tools improve our chances of finding "the needle in the haystack".
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GEOCHEMISTRY:
The search for ore deposits invariably involves looking for geochemical anomalies (areas with high metal concentrations). Like other exploration tools, geochemistry provides us with a method to systematically explore our properties by measuring the quantity of metal contained in different mediums such as rock and soil. Ore deposits were formed 100's of millions, if not billions of years ago. These deposits are commonly mechanically and/or chemically weathered over time. Therefore, analyzing the metal content of the surface soils may lead the explorer to an ore deposit. Similarly, as these ore deposits were formed, widespread traces of metal were often dumped over a much larger area (the alteration zone). At our Clearwater project, a surface soil geochemical anomaly ranging from 100 to 10,000 ppb gold, traced for a distance of 1.8 kilometres led to the discovery of the Eau Claire gold deposit.
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DIAMOND DRILLING:
Once survey data has been collected, analyzed and ranked, it's time to test the top-priority anomalies. Rock sampling and trenching allow the explorationist to evaluate surface targets in two dimensions. If further testing of these targets is warranted, diamond drilling begins. Exploration companies commonly contract the services of a diamond drilling company and generally pay by the foot or metre drilled. The diamond drill cuts and extracts a continuous cylindrical core of rock, thus testing the target in the third dimension. The diamond drill has a rotating core barrel with a diamond "bit" attached to the cutting end, which grinds into the rock formation. The rods are forced downward hydraulically, rotating at a high rate of speed. Water is pumped through the rods to cool the bit and wash away rock cuttings. The drill core is then placed into wooden core boxes or trays for the geologist to log and sample.
The exploration geologist examines the drill core and measures (logs) various parameters such as rock type, colour, hardness etc. Any intervals of "mineralized core" are split along their length with a core-splitter or cut with a diamond-bladed table-saw. Half of the core is returned to its place in the core box and the other half is sent to an assay lab for analysis. If a mineralized zone is intersected, additional drilling may be completed to determine the size and geometry of the potential ore body. Calculations are then made to determine the tonnage and grade of the potential ore body. In general, the tonnage equals the (length x width x thickness) x specific gravity of the mineralized zone.
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For more information, visit these web sites:
 www.sciencenorth.ca
www.nrcan.gc.ca
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