Native copper is non-sulphide copper. It's just straight up copper.
You can't float it, you can't process it.
You don't want it. It is soft, gummy, clogs up your mill, ends up on waste stockpiles or gravity circuits if you're lucky.
You even have to pay extra for the lab to sample it for you; they have to sieve the material that gets pulverized in the LM5 mill to find all the lumps of copper and then back-calulate volumetric abundance. Read up on Rocklands, good example.
Geology log here is effectively:0-209m - Extrusive basaltic rocks with volcanic sediments (tuffs) at 155-159m and 192-200m
209-227m - Polymictic conglomerates
Let's look at the volcanicsCopper in thick basaltic packages is leached from the basaltic rocks themselves through meteoric processes. Within the basaltic package, the copper will accumulate in voids.
It's not unusual to find native copper in basalts sitting in:
-amygdals (little voids in the basalt which were bubbles of gas when the lava solidified),
-flow-top breccias (the top of the lava gets cold and takes on a texture like a dried up mud puddle), and;
-interflow sediments (volcano stops for a few years and some sediments get deposited)
-natural fractures in the rock
None of these settings are ever big enough to host economic mineralisation, but they give an indication of what you can expect to find if the mineralisation found somewhere more expansive / permissive to forming a deposit. What are we seeing?
These are amygdals. Looks like they're filled with chlorite/sericite.
These are fractures. Elemental Cu is coming in very late and at a low-temperature.
These are logged as sediments, but they look like tuffs; volcanic ash settling out of the air.
They're calling this a mudstone, but this is a tuff with some chunks of ejecta landing in it as it gets deposited.
Let's look at the sedimentsThen we come out of the volcanics and into what looks like reduced lacustrine sediments proximal to a venting protovolcano supplying a whole lot of sulphur and creating an anoxic environment in the nearby water.
Very finely laminated reduced siltstones with pyritic beds.
No space here at all for mineralisation.
Great set of reductants, but nothing has seen a whiff of copper.
What I wish they had put in this announcement was a picture of the rocks they describe as "polymictic conglomerates" and "wackes".
If there's anywhere in this drillhole that might be suitable for mineralisation, it would be in those rocks.
Anyway, DYOR, but if I was holding some big gains today, I'd be taking some of that risk off the table.
GLTAH
