To: Claude Cormier who wrote (68743 ) 3/1/2010 10:17:17 PM From: TrueScouse 3 Recommendations Read Replies (2) | Respond to CC:<<I'm interested in clarifying just how the alluvial samples were taken in Zone 2? From the SCM website, it appears there were 83 samples from test pits roughly equally spaced on a 1,600 x 800 metre grid. There appears to be about 1 to 2 metres of overburden and then the alluvial gold zone below varies from about 0.8m to 5m in thickness. I understand that the overburden was first removed and then the test pit was dug with a backhoe. On the website it says: "A ten kilogram, vertical channel sample was then collected from the bottom of the zone to the top in each test pit." <<You ask a very important question... As you are probably aware, alluvial deposits are generally stratified in distinct zones of deposition, e.g. coarse gravels, sand & fine gravel, clean sand, sand with organics, clayey sand, etc. These strata represent different depositional environments present at the time they were laid down. For example, coarse gravel is typical of a high energy environment, i.e., fast flowing water which transports sand and finer sediments onward while dropping the heavier coarse gravel. Fine sand, silt and organics are the depositional products of lower energy environments, e.g. flood basins, the inner side of a river bend etc. Because of the different depositional environments characteristic of each alluvial strata, and because of the time difference in the erosional cycle represented by each distinct strata, the character and concentration of gold typically varies among all of the alluvial strata represented. Now to your question regarding our sampling practice. Because of the typical variation in gold character and content, each distinct stratum represented in the vertical cross section of a test pit is sampled in rough proportion to its relative thickness in the pit to make a combined sample of 10 kilos. We believe that by processing this composite sample (with each stratum represented in proportion to its thickness in the total sample column) we get a reasonable representation of the gravity recoverable gold for that pit. The contribution of each pit to the total is then weighted by the measured zone thickness.
