Dorlin Gold Project
The Dorlin Project consists of an 84 km2 Exploitation Permit for gold in the central west region of French Guiana, approximately 190 km SW of the capital Cayenne, within an area open to mining activity. The Project is accessible by road, river and small fixed wing aircraft.
The Dorlin Project is underlain by rocks typical of the greenstone belts of the Guiana Shield, which in the Yaou-Dorlin area, hosts numerous small artisanal gold workings. The area is underlain by a sequence of Proterozoic intermediate to felsic volcanic rocks belonging to the Paramaca Group that have been extensively deformed/altered and cut by felsic granitoids. Gold mineralization is mainly associated to silica-tourmaline-sulphide alteration zones that are roughly north-south striking over 7 km, steeply dipping and tabular shaped. These alteration zones are contained in schistose rocks related to strong shearing.
Reunion Gold has an option agreement to acquire a 75% interest in the Dorlin Project from Société Minière Yaou-Dorlin (SMYD), a subsidiary of AUPLATA S.A. (Euronext Growth), by delivering a feasibility study to SMYD. The option is valid for a period of five years from the date of the renewal of the Dorlin Permit. SMYD filed an application to renew the Dorlin permit in July 2015 and it is still pending.
Once the option is exercised, SMYD can maintain a 25% participating interest (“PI”) or convert it in a 5% net profit interest. If SMYD chooses a 25% PI, Reunion will have the option to acquire an additional 5% PI from SMYD for a consideration based on the NPV in the feasibility study.
Mining and Exploration History
The Dorlin Exploitation permit was exploited by artisanal miners (Orpailleurs) during the late 19th and early 20th century. The Dorlin area was an active placer mining camp, which at its peak in the first half of the 20th century had a population of 2,000 people in the village of Dorlin. The Dorlin area was explored by Bureau Minier Guyanais between 1948 and 1965, the Bureau de Recherches Géologiques et Minières (BRGM) in the 1970’s, and by BHP between 1986 and 1989. Work during these three phases included airborne and ground geophysics, geochemistry, soil and rock sampling, geological mapping and drilling (auger and diamond drill holes).
In 1994, Guyanor Ressources acquired the Dorlin and Yaou projects from BRGM/BHP, and soon after formed a joint venture with Cambior Inc. From 1990-1998, the joint venture partners completed systematic exploration on the sectors previously identified. By 1997 the objective was to bring the Dorlin project to pre-feasibility and 106 drill holes were completed on Nivre E, W S and Jadfar. Trenching was also carried out in the same areas. In 1998, a weaker gold price environment saw a decrease in exploration, but a geological model was prepared for the Nivré area for use as the basis for a mineral resource estimation.
Nivré deposit area mapNivré deposit area map with IP anomaly (red and violet indicating high chargeability), drill hole collars, mineralized sub-outcrops and artisanal workings locations.
Dorlin Nivré East Drilling SectionSection through the East Zone of the Nivré deposit with the relationship between high chargeability and reistivity anomalies with the massive silica-tourmaline-pyrite bodies mineralized in gold.
Resource classificationResource classification for colluvium/laterite domain (left) and all other domains (right).
Blue = Indicated, Green = Inferred
Mineral resource estimate
In March 2019, Reunion Gold announced a maiden mineral resource estimate for the Nivré deposit at the Dorlin Gold Project prepared by G Mining Services Inc. in accordance with Canadian National Instrument 43-101.
Indicated Resources of 18.9 million tonnes grading an average of 1.09 g/t gold containing 665,000 ounces of gold.
Inferred Resources of 26.0 million tonnes grading an average of 1.06 g/t gold containing 883,000 ounces of gold.
Notes on the Mineral Resource Estimate:
(1) Mineral Resources are reported using a gold price of US$ 1,250/ounce.
(2) The metallurgical testing was set as 93% for all types of weathering based on historical metallurgy testing.
(3) US$/€ exchange rate was set at 0.86.
(4) Cut-off grade of 0.40 g/t gold was used for colluvium/laterite and for saprolite, 0.53 g/t gold was used for transition and 0.63 g/t gold for fresh rock.
(5) Mining dilution was included (5% in saprolite, 10% in fresh rock) when producing the whittle shells but the Mineral Resources are reported undiluted.
(6) Classification of Mineral Resources conforms to CIM definitions.
(7) The qualified person for the estimate is Mr. Réjean Sirois, P. Eng, Vice President Geology and Resources for G Mining Services Inc. The estimate has an effective date of March 2, 2019.
(8) Mineral Resources do not have demonstrated economic viability. The estimate of Mineral Resources may be materially affected by environmental, permitting, legal, title, taxation, socio-political, marketing, or other relevant issues. The quantity and grade of reported Inferred Resources are uncertain in nature and there has been insufficient exploration to define these Inferred Resources as Indicated or Measured Mineral Resources.
A total of 42% of the contained gold is hosted in the laterite/colluvium and in the saprolite weathering domains. G Mining used the drill hole database which had been validated by an independent arm-length consultant comprising 26,378 assays from all available historical drilling by BHP/BRGM and Guyanor Resources totaling 24,626 meters, and 58 diamond drill holes in HQ and NQ diameter completed by Reunion Gold in 2018 totaling 6,584 meters.
Link to a detailed breakdown of Mineral Resources by zones at the Nivré deposit.
Link to complete results of the last 25 drill holes totaling 2,504.5 meters of the expansion drilling program.
Link to NI 43-101Technical Report Dorlin Project, French Guiana March 2, 2019.
resource Expansion Potential
• The Nivré deposit is open at depth and in all directions. Zones between the Nivré East/South and West Zones pits are yet to be drilled.
• Large potential to increase colluvium/laterite resources by deeper augering with limited dedicated diamond drilling.
• For the Nivré deposit, the current paucity of geotechnical information led G Mining to use conservative estimates for pit slopes (32° in colluvium/laterite and saprolite; 40° in transition; 45° in fresh rock). Despite this, the strip ratio is only 1.63 at Nivré. A sensitivity analysis by G Mining shows that a 2-degree increase in the pit slope from 45° to 47° for the fresh rock would increase the resources by giving access to high-grade gold mineralization below the current pit design. Reunion Gold expects that once all geotechnical work is completed, pit slopes will be steeper and zones of high-grade gold mineralization located immediately below the Nivré East zone current pit limits, will be incorporated into the resource.
• A sensitivity analysis to the gold price indicates a significant increase in contained ounces in the Nivré deposit with increasing gold prices.
• 91% of exploration drilling located on the Dorlin project is focused at the Nivré deposit area, and most of the gold-in-soil anomalies remain untested. A total of 11 other targets require further exploration work and drill testing.
• Better understanding of the controls of the mineralization and of the best exploration approach; the efficiency of the induced polarization geophysical method (IP) to detect the gold-bearing silica-tourmaline-pyrite facies is confirmed.