Showing posts with label Cuale. Show all posts
Showing posts with label Cuale. Show all posts

Friday, December 7, 2018

Evrim - oh dear

I was surprised that we got a PR from Evrim, I was expecting that they would wait until the new year to publish results, like our chums at GGI (link)!.

But they did publish the initial results, and they were....

not very special


how can we put this....not quite what the market was expecting...

ouch!


We could amuse ourselves with the fact that the results weren't anything special (I'll be updating a LF model over the weekend). We have a narrow zone of moderate gold mineralization at surface with a interesting (from a scientific point of view) copper zone at depth.

Oh dear
However, I'll turn your attention to this PR (link). This is where Evrim recieved ~$7.2M from Newmont, and it also tells us that they have to spend 80% (~$5.8M) of that to advance Cuale.

Will we see a massive amount of drilling at Cuale or a series of conversations to free up these funds to be spent elsewhere?

Welcome to exploration folks!

Monday, April 23, 2018

Evrim - a more detailed view

So I've compiled the data from the Cuale trenches, the Leapfrog viewer file is here (link)

left = trenches colored by number; right = trench Au assays

I've drawn on a guesstimate >1 g/t Au contour. We can see that this zone has approximate dimensions of 250m x 125m.

Why don't we focus on the very high-grade part of trench 4

Welcome to the nugget effect!


We can see that the ultra-high grade assays in trench 4 aren't repeated in the corresponding/adjacent samples in Trench 1. We can also see that they are less than 5m apart and that ultra-high grade zone is very small (6m x 6m).

We can also see that there are only 4-5 samples containing >30 g/t Au, and in the last post we saw the dramatic effect they had on the overall average grade for Trench 4. If this was drilling data, we would expect a top cut to been applied (here is a great presentation on cutting/capping high-grade samples - link)

Here is a semi-log graph of the assays - basically we're looking at how many samples (y-axis is frequency) occur within a certain assay range.

For example: In the chart below, the highest bar tells us that 38 samples returned assays between 1.5 and 2 g/t Au.

We seem to have 2 populations of samples, one centered ~1.5 g/t Au (red dashed curve) and a second at 0.1 g/t Au (blue dashed line).

So, we can see that we have very few (only 4) above 30 g/t Au, so maybe a 30 g/t top-cut could have been applied. If we do so, this is the impact:


  • Trench 4 now returns 106.2m @ 3.74 g/t Au - still good, but a >70% hair-cut


What else can we see? Look at the orientation of the trenches. They have 2 main directions:
  1. Trench 1 - NE-SW orientation
  2. Trenches 2, 3, and 4 - NW-SE orientation

Why did Evrim choose those orientations? Are there any clues?

streams = blue dashed lines
Have a look at the streams.

red and blue dashed lines = possible structural trends
Are there any other clues? Here is the Mexican Geological Survey's (SGM) map of the area (link). We can see that Cuale is in the La Gloria district.


Have a look at the San Juan Prospect (which I think is within the Evrim mineral concessions). The SGM have mapped an almost vertical NW-SE (125 strike) trending vein, and in the accompanying geological report (link - in Spanish), we also have a photo

vein - brown thingy next to the dude, probably a geologist as he is incredibly brave and handsome
I'm not saying that the mineralization at Cuale (Cerro la Gloria on the SGM map) is exactly the same as in the adjacent San Juan mine, but it gives us some additional information to make a basic, but useful interpretation from the data.

Now we can see that trenches 2, 3 and 4 are highly likely to have been excavated along some structures.

If you want to have some more fun, you can do some indicator kriging back of the envelope calculations to have a high quality resource calculation guess at contained gold.

  • Dimensions > 1 g/t Zone = 200m x 120m x 100m (depth extent)
  • Specific gravity - 2.8 tonnes/m3
  • Average grade = 1.5 g/t Au
Tonnage = 200 x 120 x 100 x 3 ~ 7.2Mt
Contained gold = 7,200,000 x (1.5/31.1) ~ 350Koz Au

These numbers are complete BS, but can be an interesting guide to potential size. Fingers crossed that they get massive thick intercepts of >1 g/t Au!










Monday, April 16, 2018

Evrim - Cuale - a quick comment

Evrim have released some stunning assays from some trenching done at Cuale (link and link), and their share price has gone crazy.

However, there may be a bit of a hangover, especially when you look at the detailed assay results  (link), where you can see that in Trench 4, you can see that they have sampled  2 very high-grade structures surrounded by a wide zone of >1 g/t Au mineralization.

red = good

If you take out these 4 high-grade intervals, this is what happens:

A bit less than 13.61 g/t Au

Still very good, but you quickly see that 83% of the Au if in just 5.8m or 5.4% of the trench.
The rest of the country rock is running >1g/t Au, so it is still a great result, but not a spectacular one.

The good news is, Evrim have identified a nice high-grade structure for drilling!!!