G'Day Jim-Considerations
1) Cuca was not mined & processed with regard OGX 's dry stacked tailings, don't think tailing from processing Cascavel contain much in the way of sulphides.
2) We don't know exactly how the grades where established either lab or Hm mill sampling results, either way
at grades up to 84 g p/t less 15% matters not, more importantly I think you may have gotton confused when you read
below -regarding sulphides -its rather clear when you re-read
See important clarifications between Cascavel & Cuca below
Quoted-
JIM NOTE-Quote A distinctive feature of the Cuca mineralized veins is the presence of sulphides (
which are mostly oxidized)- "COMPARED TO THE MESTRE LEVEL ORE ZONE".
Jim Note-still talking about Cuca here-regarding photo-Quote continued -Where the sulphides (mainly pyrite)
are oxidized, the vein has a reddish colour, when the sulphides are unaltered the vein has a
dark grey colour .
Here is the link
-CUCA'S 2nd BATCH OF PANEL SAMPLES
SEE PHOTOS BELOW
ASX/Media Release – 27 March 2018
Geologically, the Cuca Mineralized Level is located below the Mestre Level, separated by the Cascavel Dolomite layer that hosts a carbonate replacement silver-tungsten-copper mineralization (Figures 1 and 2).
The orientation of the veins is slightly different and is controlled by the main regional fabrics, dipping to the South West.
However, stretching lineation which is interpreted to control the high-grade shoots is the same as in the Mestre level,
plunging gently to the West.
Detailed geological mapping was also carried out in parallel with the sampling (Figure 3).
The gold occurrence in Cuca is similar to Cascavel and Mestre,
being mostly free and coarse gold.
The distribution of gold in the Cuca vein appears to be more consistent than the Cascavel zone
which will potentially support more consistent grade recovery during mining.
Visible gold was observed frequently in the veins exposed and sampled.
The vein shows thicknesses of
up to 50 cm (varying from 10cm to 50cm)
and is continuous along areas mapped in the historic workings.
The veins show the same strong sericite alteration halo as the Cascavel and Mestre veins (see photos below).
JIM NOTE-A distinctive feature of the Cuca mineralized veins is the presence of sulphides (
which are mostly oxidized) "compared to the Mestre level ore zone'.
Jim Note-still talking about Cuca here-regarding photo-Quote continued -Where the sulphides (mainly pyrite)
are oxidized, the vein has a reddish colour, when the sulphides are unaltered the vein has a dark grey colour (see photos below).
View attachment 1173717
Photos- Examples of the Cuca vein on the walls of the historic workings. Visible gold constantly observed in the walls and hand samples .
The Cuca old shaft is located just 350 m to the north of the Cascavel Mine portal and was part of the same mining
complex opened by the Portuguese settlers around 1720.
Other shafts and old workings can be observed in the field in between Cascavel and Cuca entrances showing a
continuous mineralized horizon at the surface (Figure 4) and suggesting the Cuca zone is present in the area
between the Cuca shaft and the Cascavel development.
Orinoco Chief Geologist Dr. Marcelo J de Carvalho commented:
"The Cuca panel sample results further increase our confidence that the Cuca-Cascavel-Mestre system represents a potentially very high grade mineralized system, which is open in all directions and characterized by several high grade mineralized veins.
All geological indications suggest this system is extensive and will support the expansion plans being developed
for the mine.
We look forward to confirming the continuity and extent of the system through the planned drilling programme.
imo-gltah
salt
