Ann: World Class Zn-Pb Resource at Teena-RXL.AX, page-95

It all depends on what your ore reserve is, and the payback period for the extra upfront capital of sinking a shaft. It all depends on the shaft's purpose - for all egress as well, or just material movement?

A simple example...

Dropping a box cut and 600m decline to reach the crown of mineralisation would cost in the realms of $25M - ore haulage costs will cost about $7/t once you commence stoping. A 600m shaft, 5000tpd winder and underground crusher/grizzly setup would set you back at least $40M, but equivalent hoisting costs would be about $4/t.

So the shaft in the above example provides a positive return on investment after approximately 5Mt are mined.

If the shaft is cut to the extent of mineralisation at ~1200, you're looking at a much bigger upfront cost, but significantly cheaper ongoing mining costs.

Resource looks good in my opinion, this will be mined for sure one day, but not tomorrow. We're not looking at the really important details, like ground conditions, reserve:resource conversion ratios of the region, surface infrastructure etc. Look at all the issues faced at Dugald River over the years for example, and it is in prime territory for mining in theory..