Orenada - breaking down the transformation Orenada has 750,000 ounces of gold resource, but 537,000 of those ounces are located within 250m of the surface. Alexandria is currently focused on the 250m area.
The transformation of Orenada should improve the economical viability of the project. We should realize meaningful increase in both grade and ounces.
Prior to 2015, Orenada was drilled as a strictly bulk-tonnage deposit. It is a disseminated deposit - and still is, but with known high grade veins within the disseminated body now. Little was known about the veins. Alexandria performed a study recently to increase the knowledge base. They drill tested the findings of the study in 2015 with 2 drill holes, and the drill results confirmed the conclusions of the study.
Firstly, ``the existence of a suite of low angle, high-grade gold-quartz veins, dipping at roughly 30o to the southwest within the Current Resources area``.
Prior to 2015, 100% of the drill holes at Orenada were drilled from the north, and oriented south. As Orenada was drilled as strictly a bulk tonnage deposit (evenly distributed mineralization), and with little knowledge of these high grade vein structures, the drill holes were essentially travelling in parallel with the veins, more or less (maybe the drill hole was more steep than the veins). The past drill holes might have crossed with the veins from time to time, but they were not necessarily colliding head on, to maximize exposure – as they were running somewhat in the same direction. Some holes were likely hitting the veins when they crossed, but single drill holes were likely not penetrating the veins in a stacked manner (and maybe not always hitting the meat of the veins).
As mentioned, Alexandria tested the findings of the study with 2 drill holes in 2015, with positive confirmation.
Alexandria moved the drills to a south position and oriented them to the north, in order to penetrate the high grade veins square on – lined up (with the veins dipping moderately southwest).
In addition to hitting the high grade veins (at least the ones lined up along the drill hole path down - there are many others in different paths that will need similar drilling), this position also allowed for long (bulk tonnage) intervals, as the lower grade disseminated gold (say, 1.0 – 2.0 g/t gold) surrounds the high grade veins.
The (two) 2015 drill holes:
OAX-15-054
158.5m of 1.43 g/t gold, which includes high grade veins of:
3.4m of 17.3 g/t Au
2.1m of 5.94 g/t Au
2.3m of 4.61 g/t Au
0.9m of 25.3 g/t Au
1.2m of 4.37 g/t Au
1.7m of 10.47 g/t Au
OAX 15-055
101.5m of .93 g/t gold, which includes high grade veins of:
1.2m of 5.92 g/t Au (within 27.5m of 1.13 Au Au)
1.4m of 4.16 g/t Au (within 46.2m of 1.33 Au Au)
1.0m of 4.00 g/t Au
1.0m of 5.61 g/t Au
As mentioned already, the old drill holes did tap the high grade veins also. They just were not positioned to hit them in a complete and stacked manner through individual drill holes. Also, the old holes were not able to test the down dip continuation of the bulk mineralization like the 2015 holes.
Here are from highlights of individual old (prior to 2015) hitting the high grade veins (a few Orenada 2 holes included also):
DH AAX-07-12 – 12.55m of 7.9 g/t Au (includes 4.05m of 21.37 g//t Au)
DH AAX-07-11 – 12.6m of 5.29 g/t Au (within 25.6m of 2.89 g/t Au, which is further within 113.1m of .94 g/t Au)
DH AAX-07-16 - 8.15m of 11.44 g/t Au (within 48.45m of 2.19 g/t Au)
DH AAX-07-32 – 8.65m of 4.07 g/t Au (within 18.45m of 2.32 g/t Au
DH OAX-08-51 – 6.00m of 4.39 g/t Au
The study also found: ``The previously unrecognized occurrence of these veins beyond the boundaries of the host shear zone, into the adjacent country rocks``
It means that these veins have pushed beyond the shear environment and beyond (or at least into) the country rocks, likely including the ultramafic rock barrier. It means less limitation and possibilities to test beyond.
In addition: ``Significant volume through the identification of a series of envelopes of gold-bearing rocks around the veins, with gold grades 2 g/t or higher (“+2 g/t isoshells”), with widths between 8 m and 20 m``
Lots of good size envelopes, with widths between 8m – 20m carrying 2.0 g/t and above gold. Very good for bulk-tonnage open pit mining.
With all this in mind, new drill targets: ``New targets have been identified outside of the traditional targets``
Here are some highlights to identify when watching the Orenada animated video:
* Freeze the video at 3:12. Light blue represents the high grade veins. You can see them slightly dipping south. You can also see the old drill holes oriented south, but in a more steep manner than the veins. Nevertheless, they are both oriented south. Also, notice the stacked nature of the veins. In addition, you can see the (two) 2015 holes positioned to connect with various veins as the drill goes down to the north. It is positioned to hit both the disseminated gold and the high grade vein gold.
* Freeze again at 3.43. The dark blue area is the 1.0 g/t (+) disseminated gold surrounding the high grade veins. It helps to add bulk. It`s good for mining. It the bedrock material didn`t have the gold then those areas would have to be trucked into waste material. Instead of spending money to remove and send to waste, they can be process and contribute to gold production (thus eat up a share of the fixed costs, subsequently lowering cash cost to produce the vein gold).
* Freeze at 4.24. Blue areas – high grade drill targets within the already established body, using the new approach.
* Freeze at 4:50. Step out drill targets – including upper right (including towards Orenada 2), lower right and lower left.
* Freeze at 4.57. The purple area is the ultramafic country rock. As you can see, the high grade veins have penetrated the rock. Alexandria lined up the new holes to test the other side of the ultramafic rock as well.
* Freeze at 5.55. Represents a better view of the step out drill areas.
Here is the link to the animated Orenada video:
https://www.youtube.com/watch?v=CGCYD4cRx1k&feature=youtu.be