We have some very good indications of the extent of mineralisation at Cascavel (and generally) despite the coarse and clustered nature of the free gold. In the following I try to develop a coherent presentation of facts to take readers through a bit of journey to develop an overview of the indications of mineralisation:
1. Historical Winzes:
A good point was made (Krum I believe) regarding the old timers knowing what they were doing. Some of the historical Winzes like Mestre date back 300 years, while some were still being mined until the lease was taken over (wouldn't upset the locals much I guess). Anyway, the issue is that while we have concentrated on the main Winzes of Cascavel, Mestre & Cuca, there are numerous other workings that we haven't explored properly (including Espanola 1.8 klm to the north -which I guess is probably one of the parallel but separate lodes ). The following diagram shows the position of some of these other workings:
As an intro for those new to the stock, there is also Espanola:
"Significantly, the tenement contains a well-known “Española” (artisanal mine – previously known as Garimpo) that produced gold from approximately 2010-2012, when Orinoco’s 30% partner at Cascavel purchased the farm-land and removed the artisanal miners.
The previous artisanal mining activities targeted gold mineralisation hosted by a low angle thrust fault immediately above and parallel to the structures that host the mineralisation at Orinoco’s 100%-owned Cascavel and Sertão Gold Project (Sertão).
The artisanal workings are located approximately 1.5km further north-west along strike from the most northerly results reported previously by Orinoco where a 2.5-tonne bulk sample from the Cuca winze returned an average grade of 27.2g/t Au. The artisanal workings consist of a series of winzes developed along approximately 200m of strike. As with Cascavel, the mineralised horizon is composed of a set of quartz veins and associated biotite alteration halo, which also carries gold grades."
"Tinteiro was discovered in May 2013, when Orinoco discovered high-grade silver and base metal mineralisation in the footwall of the Mestre zone and over the hanging wall of the Cuca zone at Cascavel.
Significant silver and base metals assays announced previously from drilling around the Cascavel area include:
CDP_025: 25.0m @ 39.2g/t Ag: including 3m @ 97.2g/t Ag from 114m
CDP_031: 4.4m @ 760.3g/t Ag: including 1.05m @ 2,510g/t Ag from 157m
CDP_014: 4.7m @ 58.6g/t Ag: including 0.85m @ 236g/t Ag from 162m
CDP_021: 17.6m @ 1,292g/t Ag & 11m @ 0.25% Cu, 16.41m from 101m
Subsequent geological mapping in the Cascavel exploration decline has shown that the high-grade silver and base metal mineralisation is related to the intersection of a series of north-east trending faults and a dolomitic unit in the footwall of the main Cascavel gold structure.
The north-west trending structures offset and therefore post-date the main gold-bearing structure indicating that these are two separate mineralising events potentially separated by millions of years.
In May 2014 rock chip samples confirmed that this mineralisation extended up to 4km away into the Tinteiro prospect, potentially indicating the presence of a large IOCG system.
Orinoco undertook a reconnaissance drilling program at Tinteiro in September 2014, which provided further evidence of a widespread mineralised polymetallic system at Tinteiro. Assays show that the fault zones are mineralised and are indicative of an alteration halo in the upper portions of an extensive mineral system."
Now this post is aimed to be more about evidence of mineralisation that affects the short to medium term prospects of OGX ...and no doubt Tintero is well into the long distance -but it's still there. Short & medium term gold supply from Cascavel / Mestre, Cuca and (in time) Espanola (and also Mateo grande) to make us cash flow positive is no doubt where the company is headed at full speed. The following also provides an overview of the Cascavel region:
2. Historical Bulk Samples
Recent reports may lead to the conclusion that our recent 15x 1 tonne bulk samples are a novel revelation. Now don't get me wrong, they are more than welcome as they support the efficacy of using a hammer-mill, but there have been plenty of bulk samples before these latest samples.
Cascavel & Mestre (2012):
Cuca (2012):
An important distinction to make is that these original bulk samples were taken only from the existing historical winzes (because access was required to physically take them).
3. Historical Drill Results
The historical drill results provide a fantastic opportunity understand the scope of the mineralisation that has been found in both a two dimensional view (understanding the distances involved), but also in a three dimensional view to understand the different layers of mineralisation (gold bearing quaertz lodes), and also the grades or at least evidence of gold.
Lets jump to the most important issue when it comes to drilling for coarse and clustered free gold mineralisation:
Without trying to quantify any drill results ...what we can see is that if you find any gold particles in your drill core when drilling for coarse free gold ...it's very good news. If you find any gold particles in your coarse AND CLUSTERED free gold ...it's fantastic news:
These results speak for themselves!
This post gives a bit of an idea on mineralisation intercepts:
4. JORC MRE (Mineral Resource Estimate) & ET (Exploration Target)
I'm not going to rave on too much about this ...except to say that the JORC MRE was compiled after dozens of wall samples were taken and assayed and was overseen by independent consultant Mining Plus who also prepared the RE. The report is over 40 pages in length and will have many answers for geos and statisticians alike. In light of the fact that the results from the 15x recent 1 tonne samples tend to confirm (exceed) the average grade used in MRE, I think it is safe to say that the evidence suggests that the MRE is conservative (as would be expected).
I've noticed an anomaly in the RE figures and this caused me to use my own figure for ET Ounces (who can figure out the anomaly?):
5. Recent Bulk Samples
The recent bulk samples are in an entirely different category to the historical bulk samples (but not the MRE), because they were taken from the more recent mine development -thus validating the fact that high-grade mineralisation is widely distributed throughout the mine:
35 Samples so far:
To give us an idea of where things are this next one shows the approximate position of Mestre & Cascavel Winzes and the JORC MRE, with a background of the 35 samples totalling 40 tonnes:
If the planned bulk samples from the northern part of the mine also prove to be high-grade (or even 10 g/t) then it will be another fantastic result and further confirmation of OGX viability as I see it.
6. Drill results -the big picture.
In this part ...I post a series of screen shots on a G0ogle Earth that show close detail of drill results and then progressively zoom out to provide an idea of scope.
Some of the maps were designed to be more conceptual in nature, so take the locations wit ha grain of salt. Some maps clearly had minor location (survey) inaccuracies, but other were able to be referenced against physical features. They cross-reference pretty well, and essentially are for factor-of-scale purposes, not survey work.
Mine development to end of November with Drill CDP-004 (with drill data) and distance to development.
Please note the various parallel lodes as evidenced by the multiple zones of mineralisation in the drill results. I think it looks probable (logical) that the mineralised drill intersections are linked between drill holes -but with unknown continuity.
Keep in mind that we are currently mining one lode only (Cascavel - Metre) -with consideration being given to mining Cuca in the next few months.
While we are at it ...lets not forget CDP-052 some 1.2 klm down dip from Cascavel and including 3m package of mineralisation:
This figure shows CDP 009, 004 & 005 and distances with JORC MRE & ET plan and also CDP_052 in a conceptual position (because coordinates not supplied -just 1.2k down-dip)
Following are a variety of maps that show different intercept info at different times:
2015 Drill data with Nov 17 mine development superimposed on Google Earth
Lets not forget CDP-002 with visible gold in un-assayed half core.
Gold drill results with JORC MRE & ET & Nov 17 mine development superimposed on Google Earth (zoomed out)
Another important point as I see it is that CDP-028 has never been shown on any maps, (perhaps because it is too far away from current operations and too much close detail would have been lost to include it), but it appears to increase the strike length.
New tenements map overview with MRE & ET & Nov 17 mine development superimposed including Mato Grande (rarely mentioned)
I think even the most cynical human will agree that the issue is not whether or not there is sufficient gold (and silver etc) mineralisation ...but rather ...how do we mine it efficiently and expeditiously.
It looks as though we are well on the way.
If you are new to this stock, it may well be worth your time to study the info that has taken days to collate. You could give yourself a nice head-start.
Cheers and all the best with the upcoming Big Harry Ann.
SJB
OGX Price at posting:
10.0¢ Sentiment: Buy Disclosure: Held
