- 1857: Identification of pyrite in Wainisavu creek area.
- 1935 – 1937: Discovery of Wainisavu mineralisation by Whitehall Exploration Ltd.
- 1968 – 1980: Exploration by the Viti Copper Joint Venture (Central Mining Finance, AMAX, CRA)
- 1978 – 1980: Mining pre-feasibility study undertaken and completed by Viti Copper JV (managed by CRA)
- 1983: Exploration tenements expire (SPL 1014)
- 1986: Exploration tenements granted to WMC (SPL 1238)
- 1986 – 1989: WMC exploration for gold until March
- 1991: Exploration tenements granted to Placer Pacific Ltd (SPL 1367)
- 1992: SPL 1352 granted to Placer for the purposes of evaluation of Waisoi deposits
- 1993 – 1994: Placer complete economic evaluation study on Waisoi deposits
- 1994 – 1995: Placer explore for additional higher grade mineralisation (>0.5%Cueq) to improve mining project economics
- 2001 – 2007: Nittetsu Mining acquire exploration tenements (SPL 1420) and undertake exploration activities
- 2005: Negotiations begin between Nittetsu and Newcrest Mining Limited to form a joint venture
- 2007: Joint Venture agreement finalized
- 2008: Namosi Joint Venture commences exploration of SPL 1420
- 2010: SPL 1420 Renewal
- 2011: SPL Renewal
- 2015: SPL extended for another 5 years.
