People might be better just sticking to a more geologically accurate description of what a supergene enrichment zone is (see below). Contrary to what mainholm has described the metals are enriched as they are dissolved by water that moves (percolates) down through the surface layer of the ore deposit (the oxide zone) and they become enriched near the water table. The water can also carry the metals lower and create secondary sulphide minerals. Typically the grade of ores in the supergene zone is higher than the primary ore below. Sorry mainholm, sometimes its better not to dumb things down too much. Very high and spectacular grades today in this announcement but the 8m width of the mineralisation might be overstated due to averaging? I'd like to see the assays for the individual metre splits so I can see how wide the ore body (mineralisation) actually is. The other drill intercepts are all likely to have true widths of less than 2m and I suspect that is also true for the wider reported intercept. Maybe this is why the market hasn't reacted as might be expected, the grades are great but the tonnages might not be huge. I'm also with eastwest101, I've probably missed the boat a bit for the juicy gains. Good luck all. Esh
Ore Deposits Formed by Oxidation and Supergene Enrichment
When ore deposits are exposed to the oxidation zone they are weathered and altered with the country rocks.
The surface waters oxidize many ore minerals and yield solvents that dissolve other minerals.
An orebody thus becomes oxidized and generally leached of many of its valuable materials down to the groundwater table, or to depth where oxidation cannot take place.
The effects oxidation may, however, extend far below the one of oxidation.
As the cold, dilute, leaching solutions trickle downwards, they may lose a part or all of their metallic content within the zone of oxidation to give rise to oxidized ore deposits.
The oxidized or near-surface part of an orebody is made colorful due to the oxidation of sulfides to oxides and sulfates.
As the down trickling solutions penetrate the water table, their metallic content may be precipitated in the form of secondary sulfides to give rise to a zone of secondary or supergene sulfide enrichment.
The lower, unaffected part of the orebody is called the hypogene zone.
In some places the supergene zone is absent and in rare cases the oxidized zone may be shallow or lacking (as in some glaciated areas undergoing rapid erosion).
Special conditions of time, climate, physiographic development and amenable ores are necessary for the process of oxidation and supergene enrichment to be effective.
Such ores occur in most of the non-glaciated land areas of the world.
ERM Price at posting:
16.5¢ Sentiment: None Disclosure: Not Held
