Oko West Project Guyana

OKO WEST PROJECT

GUYANA

OKO WEST PROJECT 

Background

Reunion Gold's Oko West Project is a brand-new gold discovery in northwest Guyana located south of the historical "Oko" gold district. In 2020, Reunion Gold's geochemical survey, trenching, and initial drill program discovered and confirmed the presence of gold mineralization in shear zones along the contact between a greenstone belt assemblage and a granitoid unit on the east side of the project area. The mineralization coincides with a 6 km long gold-in-soil geochemical anomaly. The northern 2.5 km of strike length of that geochemical anomaly, where most of the drilling to date has taken place, is being referred to as the Kairuni zone. The southern 3.5 km of that geochemical anomaly (called the Takutu zone) remains largely untested and represents one of several priority exploration targets on the project. An ongoing drill program at the Kairuni zone has confirmed gold mineralization in the saprolite and unweathered rock, showing good continuity along its 2.5 km strike. The deepest hole drilled intersected strong gold mineralization at 575 m vertical depth, and the Kairuni zone remains open along strike and depth. 

Location

 

The Oko West Project is in the Cuyuni Mining District, some 95 km west of Georgetown and accessible by the Puruni laterite road and trails from the towns of Bartica and Itabali on the Mazaruni river (Figure 1). The Puruni road leads to the Toroparu mine and is currently being rehabilitated.

Mineral rights and agreement

The Oko West Project comprises 10,880 acres of mineral rights held by Guyanese entrepreneurs (Figure 2). Reunion entered into agreements entitling it to conduct exploration work and acquire a 100% interest in the project area. 

Geology and mineralization

 

The Oko West Project area is underlain by a greenstone belt assemblage of rocks from the Barama Group, consisting of volcanics, clastic sediments and granitic plutons of Proterozoic age. Reunion Gold discovered an entirely new gold deposit in these rocks at the eastern edge of the project area  (Figure 2).  Gold mineralization is hosted by rocks strongly deformed by at least two tectonic events, causing intense fracturing and shearing and creating large and porous zones favourable for the emplacement of mineralizing fluids. Carbonate and sericite alteration accompanied by pyrite in quartz veining and quartz stockworks are typically associated with gold mineralization.

Exploration program

In 2019, Reunion Gold launched its exploration program, including geological mapping, stream sediment geochemistry, and a detailed airborne magnetic and radiometric survey. 
 
Geochemistry


In 2020, Reunion Gold did a soil geochemical survey with samples taken every 50 m along lines spaced 200 m apart. The survey defined a gold in soil anomaly with a strike length of approximately 6 km. The anomalies coincide with shear zones associated with the geological contact between a sequence of volcano-sedimentary rocks and a granitic pluton to the east (Figure 3).

Trenching

The Company followed up the geochemical survey with a mechanized trenching program designed to test the geochemical anomalies at shallow depths. The trenching program consisted of excavator-dug trenches with channel samples collected from weathered rocks on the trench walls. Thirty-three trenches were excavated at approximately 200 m intervals over the northernmost 2.5 km of the gold soil geochemical anomaly (the Kairuni zone), totalling over 7,500 linear meters.  Figure 4 and table 1 report the assay results from these trenches. The trenching program successfully confirmed that gold mineralization extends into the weathered bedrock (saprolite).

Drilling

On February 18, 2021, the Company reported assay results from the completion of its initial 1,000-meter diamond drilling program. This program demonstrated the vertical continuity of gold mineralization down to 100 m into the saprolite below trenches 4, 9, 18 and 19.

The encouraging results from the initial drill program prompted Reunion Gold to launch a robust drill program to systematically test gold mineralization's vertical and lateral continuity in the 2.5 km long Kairuni zone to a vertical depth of 250 m. The drilling program was initially designed with east-west drill "fences" spaced every 100 meters. This program began on June 17, 2021, with one diamond drill rig, and, on July 25, the Company added a reverse circulation drill. In October 2021, the Company added a second diamond drilling rig. In April and June 2022, it added a third and fourth diamond drill rigs, planning to close the spacing between drill holes to a 50 m grid. As of June 2022, the Company had completed 121 diamond drill holes totalling approximately 20,000 meters and 180 reverse circulation drill holes totalling about 15,000 meters, mainly in the Kairuni zone (Figures 5 and 6).

 

The drilling completed has shown excellent results, indicating continuous gold mineralization over the 2.5 km long Kairuni zone and reaching a vertical depth of ~575 m in hole D22-112 (Figure 9). This hole successfully tested the depth extension of the Kairuni zone in block 4 with a significant intersection of 3.68 grams per ton of gold (g/t Au) over 71.15 meters. Hole D22-112 shows the interbedded clastic sediments and volcanoclastic rock units typically hosting gold mineralization in the Kairuni zone. The total length of composites within this zone, ignoring unmineralized intervals, is approximately 134 meters (the lengths referenced here do not represent true width). This hole also represents one of the best holes reported to date in terms of grade, length and vertical depth. 

The continuity and depth extension of the Kairuni zone are illustrated in the plan map and longitudinal sections shown in Figure 5 (based on a gold grade block model with a 0.3 g/t cutoff). Figure 6 shows a geological map of the Kairuni zone highlighting the intercepts from the June 13, 2022, press release (in green). Figures 7 to 11 show geological cross-sections of the mineralized rocks in the Kairuni zone. Tables 2 and 3 show the composite intersections and collar locations for diamond drill holes and RC holes.  

Other targets

The current exploration program also includes proposed scout drilling to test three additional priority target areas on the Oko West Project, as shown in Figure 12. These targets include the Takutu zone, which represents the southern 3.5 km of the gold in soil geochemical anomaly, lying upstream from an area of significant alluvial workings. The Bryan target zone (also identified by the number 2) covers the potential hard rock source for an area of significant alluvial gold mineralization that has been mined downstream at the center of the project area. The third target area, named the Carol zone, is immediately west of the Kairuni zone, where several gold soil anomalies are found over an area underlain by favourable geology.

Figure 1: Oko West project location showing roads and regional geology

Oko West project location showing roads and regional geology

Figure 2: Oko West Project area outline and geology showing soil geochemical anomaly.

Figure 2: Oko West Project area outline and geology showing soil geochemical anomaly.

Figure 3: Detail of soil geochemical anomaly divided into the Kairuni and Takutu zones.

Figure 3: Detail of soil geochemical anomaly divided into the Kairuni and Takutu zones.

Figure 4: Map of soil geochemical anomalies and highlighted trench results.

Figure 4: Map of soil geochemical anomalies and highlighted trench results.

Figure 5: Gold grade (g/t) voxel block model of the Kairuni zone shown as plan and longitudinal section (looking west) using 0.3 g/t gold cutoff grade and 8 by 8 m blocks. Planned DD holes are red dots, and planned RC holes are blue squares.

Figure 5: Gold grade (g/t) voxel block model of the Kairuni zone shown as plan and longitudinal section (looking west) using 0.3 g/t gold cutoff grade and 8 by 8 m blocks. Planned DD holes are red dots, and planned RC holes are blue squares.

Figure 6: Plan map of the Kairuni zone showing geology, mineralized zones and drill holes with results announced in the June 13, 2022, press release shown in green. Reunion Gold identified six exploration "blocks" within the Kairuni zone for ease of reference.

Figure 6: Plan map of the Kairuni zone showing geology, mineralized zones and drill holes with results announced in the June 13, 2022, press release shown in green. Reunion Gold identified six exploration "blocks" within the Kairuni zone for ease of reference.

Figure 7: Cross-section 701950N. 

 
Figure 7: Cross-section 701950N. 

Figure 8: Cross-section 701850N.

Figure 8: Cross-section 701850N.

Figure 9: Cross-section 701800N. Hole D-112 reported the deepest intersection so far in the deposit. 

Figure 9: Cross-section 701800N. Hole D-112 reported the deepest intersection so far in the deposit. 

Figure 10: Cross-section 701750N. 

Figure 10: Cross-section 701750N. 

Figure 11: Cross-section 701700N. 

Figure 11: Cross-section 701700N. 

Figure 12: Three priority exploration targets at the Oko West Project

Figure 12: Three priority exploration targets at the Oko West Project

Tables 1-3 show detailed trench, diamond drilling, and reverse circulation drilling results can be found in the links below labelled table 1: Trenching results, table 2: Diamond drilling composite results, and table 3: Reverse Circulation drill composite results.

 

Link to: Table 1: Trenching results

Link to: Table 2: Diamond drilling composite results

Link to: Table 3: Reverse Circulation drill composite results

  

Notes to the tables of composite results

 

Composite drill and trench intersections calculations:

  • Minimum composite grade of 0.3 g/t    

  • Minimum composite length of 2 m 

  • Cut off interval for inclusion is 0.3 g/t 

  • The maximum length of internal waste is 7 m   

  • Gold grades are uncapped.   

  • Mineralized intersection lengths are not necessarily true widths.

Sampling and analysis:

 

  • Trench samples are channels taken horizontally and continuously in in-situ weathered rocks (saprolite) at regular intervals on trench walls. Reunion considers channel samples as sub-horizontal "drill holes" given their continuity and representative rock mass.

  • Diamond drill samples consist of half of either HQ or NQ core taken continuously at regular intervals averaging 1.4 m, bagged, and labelled at the site core shed. 

  • Reverse circulation drill samples are obtained from a rotary splitter attached to a Metzke cyclone, weighed, bagged, and tagged at the drill site. 

  • Samples are shipped to the Actlabs certified laboratory in Georgetown, Guyana, respecting the best chain of custody practices. At the laboratory, samples are dried, crushed up to 80% passing 2 mm, riffle split (250 g), and pulverized to 95% passing 105 μm, including cleaner sand. 50 g of pulverized material is fire assayed by atomic absorption (AA). Initial assays with results above 3,000 ppb gold are re-assayed with a gravimetric finish. Certified reference materials and blanks are inserted at 5% of samples shipped to the laboratory. MSALabs, another certified laboratory in Georgetown, tests umpire samples generated by Actlabs.

  • Assay data is subject to QA/QC using acQuire software and management by an independent consultant.

Other parameters:

 

  • Drill and trench collar locations were surveyed by professional Guyana land surveyors using differential GPS and total stations.  

  • Diamond and reverse circulation drill holes are surveyed by down-hole equipment. 

  •  Diamond drill core is oriented as frequently as possible.