Ann: Mineral Resource & Ore Reserve Statement as at 30 June 2023, page-8

Hi helpmenow

The strike zone in main pit is 30 metres wide and runs for the 2km length of main pit.

As Peter Kerr has stated "move one metre either side and one will entirely miss the strike zone.

The 30 metre wide strike zone is currently pressed hard up against the northern wall.

To gain better access to the 30 metre wide strike zone the angle of repose of the northern wall was increased from 75 degrees to 80 degrees. The repose angle was changed a couple of years ago and was reflected in an increase in the mineral resource statement at the time.

One could apply basic trigonometry to calculate at what depth the northern wall would be sitting entirely on the 30 metre wide strike zone . . . but if one looks at the schematic elevations of the mineral resource, one can see that the resource is sloping to the sea (towards the seawall), so as we go deeper, the 30 metre wide strike zone slowly moves away from the northern wall side of the pit towards the sea wall side of the pit.

Also the schematic elevations of the resource show that the resource is moving away from the northern wall at an angle somewhat less than the 80 degree angle of repose of the hanging wall, which will effectively move the 30 metre wide strike zone from being hard up against the northern wall, which will actually make minining more accessable as we go deeper . . . until one day that the angle of repose of the northern wall and the angle of repose of the seawall intersect, which has been modelled to 215 metres. It has taken 70 years of mining to get to the present depth of 125 metres.