Peel Mining

May Day Project

Project Snapshot


Resource Definition Drilling


~105km south-southeast of Cobar. Close proximity and serviced by the Kidman Highway.

Area Size



100% Peel Mining Limited


Gold, Silver, Zinc & Lead

  • Located over the previously mined May Day Pit (mined in late 1990s) and the May Day gold-silver-copper-lead-zinc deposit (discovered in 1898), the Mining Lease 1361 “May Day” was initially granted Imperial Corporation Limited. Peel Mining Ltd obtained the lease in November, 2009.

    2,398 oz of gold was recovered from mining conducted by Jason Mining in the mid-1990s. A small open pit to ~50m below surface was established. Return occurred from approximately 81,000t of high grade ore averaging 3.35 g/t Au, and 102,000t of lower grade ore averaging 1.3 g/t Au. (Exact figures regarding production are unknown, and technical problems associated with an unproven recovery process (Vitrokele) was encountered.)

  • The Indicated Mineral Resource Estimate (MRE) for the May Day deposit consists of 1.07 Mt at 1.02 g/t Au, 26.3 g/t Ag, 0.74% Zn, 0.50% Pb. The MRE was based on drilling, NSR and mining and processing parameters supplied by Peel. Drilling in the May Day area comprises 169 open-hole percussion holes, 106 RC holes and 21 diamond holes for a combined 23,947m of drilling completed by Peel and previous property owners. The modelling dataset include only RC and diamond drilling. The mineralised domain estimation dataset is dominated by composites from Peel’s RC and diamond sampling which contribute 69% and 16% of the remnant data respectively. RC and diamond drilling by Epoch Mining during the 1980’s contribute 12% and 2% respectively.

    May Day Indicated Resource
      Cut off $NSR Kt Au g/t Ag g/t Zn % Pb %
    Open Pit Oxide $27/t 510 1.03 20.4 - -
    Sulphide $37/t 390 1.00 28.2 1.31 0.84
    Subtotal   900 1.02 23.8 0.57 0.36
    Underground (Sulphide) $80/t 170 1.03 39.4 1.67 1.21
    Combined 1,070 1.02 26.3 0.74 0.5

    The MRE has been reported in accordance with the JORC Code (2012 Edition) and is reported within an optimal pit shell, and optimised stope shapes generated at appropriate relevant NSR cut-offs. Table 1 presents the estimates with the open pit components subdivided by oxidation zone. The figures in this table are rounded to reflect the precision of the estimates and include rounding errors.

    (ASX Announcement- May Day indicated Mineral Resource Estimate, 31th March 2021)

  • The Cobar Basin developed as four deep-water troughs bordered by shallow-water shelves. The southern parts of the Basin, where the May Day deposit is located, are covered by the Mount Hope and Rast Troughs which were filled with sediments, volcaniclastics, and volcanics of bi-modal nature. May Day is thought to be a deformed VMS deposit.

    The mineralised zone can be found in proximity to the contact between the sediments (the Upper Amphitheatre Group) and the volcanics (the Mount Halfway Volcanics) within highly sheared-altered (talc-sericite-chlorite-carbonite) zones. The primary sulphides are pyrite-sphalerite-galena-chalcopyrite. Assays received to date show strong, continuous, and wide gold-polymetallic intercepts, confirming substantial true width (~25m) at relatively shallow depths. A high-grade core proximal to the hanging wall is evident with an approximate true thickness of up to ~12m. Results compliment previously received assays which also confirmed good down-dip continuity (minimum 180m down dip continuity from the base of the pit) of the May Day mineral system.

    May Day, The Upper Amphitheatre Group

    The Upper Amphitheatre Group contains interbedded shales-siltstones-sandstones of thin to moderate bed thicknesses. Locally the sediments can host tephra, with rhyolitic to rhyodacitic tuffs compositions, these are considered to be the stratigraphical equivalent to the Mount Halfway Volcanics. The depositional environment for this group is interpreted to have been deep marine environment turbidites.

    May Day, The Mount Hope Volcanics

    The Mount Halfway Volcanics at May Day are predominately made up of rhyolitic to rhyodacitic lavas with porphyritic tuffs. Localised sedimentary based units of interbedded sandstones and siltstones can be commonly found too. The depositional setting has been interpreted to have been deep marine with the rocks having been deposited as pyroclastic ashflows with interbedded turbidites. The Mount Halfway Volcanics are conformably overlain by and interfinger with the Upper Amphitheatre Group.

    The Shear Zone

    Due to the steeply plunging nature of the structures at May Day, it is likely that the deformation which lead to the shearing is associated with the Cobar deformation. It has been observed that the highly mineralised intervals contain intensely sheared zones, where the initially lithology can frequently no-longer be distinguished due to the level of shearing and associated synchronous alteration. Mineralised quartz veins were likely developed coevally with the aforementioned deformation, and it is considered that the veins likely formed steeply plunging shoots.