The "ore" blocks, in Magenta, clearly show discontinuities and...

The "ore" blocks, in Magenta, clearly show discontinuities and stacked lenses. In an open pit situation this is "acceptable". However, in an UG situation it would probably add to the cost of mining where only detailed studies could show if mineralisation had viable economics.

Sure, but this is still very shallow. Look at the slope. Easy to gain access from the side. And remember they are using the Room and Pillar method when not open pit. This is a cheap method.