CÔTE D’IVOIRE - DIDIEVI PROJECT
Today Cote d’Ivoire is among the fastest-growing economies in Africa, and one of the most dynamic in West Africa. Côte d’Ivoire introduced a progressive new mining code in 2014, and on-going infrastructure improvements are making the country one of the more investor-friendly countries in Africa. There is a strong desire to diversify the economy with gold and other mineral products. Exporting electricity is playing an increasing role in this diversification. Underexplored until the last decade it is finally delivering a plethora of exciting new discoveries.
The country has 6 major producing gold mines and a number of near-term development projects including Ity 4.5 Moz and +1Moz Agbou (Endeavour), Yaoure 3.4 Moz and Sissingue (Perseus), Tongon 2.7 Moz (Barrick) and Bonicro (Allied Gold). Other mineral commodities that offer the potential for economic development in Côte d’Ivoire include diamonds, petroleum, natural gas, copper, iron, cobalt, bauxite, tantalum, lithium and silica sand.
Didievi Project, Côte d’Ivoire
The Didievi Project (391km2) is located within the underexplored and emerging Oume-Fetekro Birimian greenstone belt. The belt hosts Allied Gold’s Bonikro/Hire (+3Moz) and Endeavor’s Agbaou (+1Moz) gold mines to the south and the recent +2.5Moz Fetekro discovery announced by Endeavour Mining to the north.
This strategic project straddles a major structure in a belt with all the selection criteria required for multiple large gold deposits. Past work on the property has considerably de-risked the discovery process. Historical exploration on the permit has delineated one significant gold system at Blaffo Gueto and seven untested advanced gold prospects. The project presents both brown- and greenfields opportunities with the potential to deliver large economic deposits (see Figure).
Previous exploration between 2006 and 2011 was conducted by Glencore and Equigold and then by Lihir and Newcrest. Work by Glencore and Equigold focused on the western part of the current permit and consisted of acquisition of high-resolution airborne magnetic and radiometric data, broad (800m x 50m & 200m) spaced geochemical soil sampling followed up with infill sampling on 9 discrete areas, limited trenching, rock chip sampling, RAB, RC and diamond drilling. The western half of the current Didievi permit is covered by high resolution airborne magnetic/radiometric data. Pole-dipole, dipole-dipole and gradient array induced polarization and ground magnetic geophysical surveys were undertaken at Blaffo Gueto (see Figures 4-6).
Equigold made two discoveries, Blaffo Gueto and Pranoi. From 2008, work focused almost entirely on the Blaffo Gueto Prospect.
A total of 312 RC holes and 23 diamond holes were drilled at Blaffo Gueto for 26,850m and 4,275m respectively (best intercept 83.3m @ 3.3g/t Au from 166.9m - see below). Work at Blaffo Gueto delineated a significant structurally controlled gold system charaterised by intense alteration and broad, high-grade gold intercepts. Mineralisation is complex, probably long lived and multi episodic, located in different structural settings and hosted by a variety of lithological units. Gold mineralization is typically associated with sericite-albite-carbonate-quartz/silica-pyrite-pyrrhotite ±chlcopyrite ±arsenopyrite ±Fe(Ti) oxide alteration assemblages. Host rock are typically strongly altered and deformed. Gold mineralized occurs over very wide intervals (+200m across strike in the main zone) and return some spectacular intercepts, including:
DDD001: 83.3 m at 3.3g/t Au from 166.9 m incl. 18.0 m at 12g/t Au
DDD013: 89.0 m at 3.0g/t Au from 0 m incl. 23.0 m at 9.5g/t Au
DRC130: 43.0 m at 4.3g/t Au from 57 m incl. 17.0 m at 9.5g/t Au
DRC138: 69.0 m at 2.9g/t Au from 31 m incl. 37.0 m at 4.9g/t Au
DRC208: 37.0 m at 7.7g/t Au from 42 m incl. 24 m at 11.0g/t Au
Two main gold zones, BG Main and BG South West have been delineated to date, both strike roughly NNE and while anastomosing both are seemingly, sub-vertical to very steeply SE dipping with a suspected steep NE plunge component to the high-grade core. Within the BG main zone (+600m strike x 200m wide) there are two main subparallel NE trending high-grade gold zones with the potential for high-grade EW linking structures. While some excellent work has been done by Equigold this was almost entirely focused on Blaffo Gueto Prospect and on the high-grade portion of the deposit. Geometry, structural controls and gold paragenesis of gold mineralization are still poorly understood.
BG Main is essentially open along strike and down dip. Significant mineralization and alteration located within a number of holes between BG Main and BG South West remains unexplained and open in all directions (DDH03 88m at 1g/t incl. 12m at 2.6g/t and 12m @ 2.8g/t) and DRC124 (63m at 1.06g/t incl. 21m @ 2.4g/t Au).
In the near vicinity of the Blaffo Gueto Prospect are a number of historically notable drill intercepts (with respect to grade, structure and alteration) outside the two main zones that have yet to be followed up and are open along strike and at depth. Intercepts often have high-grade cores with supporting mineralization. The two most obvious targets, BG South, a single traverse DRC205 15.0m at 1.6g/t Au from 61.0m, and BG South East, two traverses of 4 and 5 RC holes each drilled 400m apart with no drilling along strike to the NE, returned very broad moderate grade anomalism in the majority of holes on both sections.
Only a portion of the Blaffo Gueto gold-in-soil and coincident chargeability / resistivity induced polarisation anomalies spacially associated with mineralization appear to have been drill tested to date (see Figure 6). Drilling at Blaffo Gueto Main (locally grid 3000mN) has shown laterite cover to 30m in places this would obviously have an impact on surface geochemical response.
There are multiple walk up drill targets both within the Blaffo Gueto prospect itself, as well as in the near prospect environment.
High resolution magnetic / radiometric data and first pass broad spaced (800m x 50 & 100m) soil sampling and infill sampling have defined a number of very large robust gold-in-soil anomalies and provide an excellent basis for further work and defining additional quality drill targets. Recent targeting work has defined an additional seven high quality coincident structural/magnetic/geochemical anomalies that require immediate drill testing.
Work to date does not include detailed geological and regolith mapping as part of the surface geochemical survey design and interpretation of geochemical data. Regolith interpretation and mapping will be used to define future areas not previously considered suited to surface sampling and to reinterpret existing data. Based on knowledge of BG and other mineralized systems in the Birimian of west Africa there is scope to use multielement geochemistry and XRF in soils and drilling to define pathfinders and vectors to mineralization.
At Pranoi, a total of 73 RAB (2,368m) were drilled on 7 traverses over 600m strike length and followed up by 7 RC holes (940m). Impressive shallow broad RAB intercepts of 12m @ 5.60g/t Au from 24m; 15.0m @ 1.74g/t Au from 0m; 11.0m @ 1.38g/t Au from 21m and 8.0m @ 4.35g/t Au from 0m when followed up by RC returned 13.0m @ 2.65g/t Au from 8m; 3.0m @ 3.40g/t Au from 11m & 10m @ 1.33g/t from 41m inn the same hole. The geometry and source of shallow mineralization remains enigmatic and is not properly understood and will require additional targeted drilling in the next field season.