TSX:  LMC  $3.25  Gold:  $1586.45/oz
TSX-V: LMC $3.25  Gold: $1586.45/oz

RDM Mine

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The RDM mine is located in Minas Gerais State, Brazil, about 560 kilometres north of the state capital city of Belo Horizonte. The mine area covers approximately 22,600 ha and is accessible by air and road. It was acquired by Brio Gold in April 2016 and subsequently acquired by Leagold in May 2018. The operation is a conventional open pit mine with a 7,000 tpd carbon-in-leach (CIL) plant. The RDM mine commenced production in early 2014. Average life of mine production at RDM is estimated to be approximately 98,000 ounces of gold per year over a nine-year mine life.

Geology and Mineralization

The RDM gold deposit occurs in the north-south trending Araçuaí Fold- Thrust Belt along the eastern margin of the São Francisco Craton, a major Archean-age basement block which underlies more than one million square kilometres in eastern Brazil. The Araçuaí Fold Belt is 15 km to 45 km wide and consists of a series of meta-volcanic/meta-sedimentary rocks of late Archean to late Proterozoic age.

The principal host for the gold mineralization is the quartz-muscovite schist of the Riacho dos Machados Group. The mineralization occurs in a belt of hydrothermally-altered rock developed along a district-scale shear zone. Mineralization occurs in the hydrothermal/shear zone and gold grades are closely related to the sulphide content, especially arsenopyrite.

Reserves and Resources

Mineral Resources (May 31, 2018)

Classification Tonnes (kt) Gold grade (g/t) Contained gold (koz)
Measured – open pit 3,195 0.77 79
Indicated – open pit 27,731 0.96 853
Measured and Indicated – open pit 30,926 0.94 932
Inferred – open pit 7 1.42 0
Measured – underground 0 0 0
Indicated – underground 5,239 1.58 266
Measured and Indicated – underground 5,239 1.58 266
Inferred – underground 8,297 1.50 401
Indicated – stockpiles 3,137 0.61 62
Total Measured and Indicated 39,303 1.00 1,259
Total Inferred 8,305 1.50 401


  1. CIM (2014) definitions were followed for Mineral Resources.
  2. Mineral Resources are inclusive of Mineral Reserves.
  3. Open pit Mineral Resources are reported at a cut-off grade of 0.30 g/t Au.
  4. Underground Mineral Resources are reported at a cut-off grade of 1.0 g/t Au
  5. No minimum thickness was used in the resource estimation.
  6. Mineral Resources estimated using US$1,500/oz gold price, exchange rate of R$3.70 = US$1.00 and constrained by a pit shell.
  7. Mineral Resources that are not Mineral Reserves do not have demonstrated economic viability.
  8. Totals may not add due to rounding.


Mineral Reserves (May 31, 2018)

Classification Tonnes (kt) Gold grade (g/t) Contained gold (koz)
Proven – open pit 2,510 0.88 71
Proven – stockpiles 3,137 0.61 62
Total Proven 5,647 0.73 133
Probable– open pit 19,079 1.08 656
Total Probable 19,079 1.08 656
Proven and Probable – open pit 21,589 1.05 728
Proven and Probable – stockpiles 3,137 0.61 62
Total Proven and Probable 24,726 0.99 789


  1. CIM (2014) definitions were followed for Mineral Reserves.
  2. Mineral Reserves were generated using the May 31, 2018 mining surface.
  3. Mineral Reserves are reported at an open pit cut-off grade of 0.40 g/t Au.
  4. Mineral Reserves are reported using a long-term gold price of US$1,200/oz and exchange rate of R$3.70 = US$1.00.
  5. Mining dilution of 5% and 95% mining recovery.
  6. Process recovery of 90%.
  7. Totals may not add due to rounding.


Source of Technical Information and Qualified Persons

For further information regarding the mineral resource and mineral reserve estimates at RDM, please see the Company’s technical report prepared in accordance with NI 43-101 entitled “Technical Report on the Riacho dos Machados Gold Mine, Minas Gerais, Brazil” by Roscoe Postle Associates Inc. (RPA), and dated November 20, 2018 with an effective date of May 31, 2018. Hugo M. Miranda, MBA, ChMc (RM), Mark B. Mathisen, C.P.G. and Kathleen Ann Altman, Ph.D., P.E., are the Qualified Persons that prepared or supervised the preparation of the information that forms the basis for the written disclosure regarding RDM.