Ann: World Class Zn-Pb Resource at Teena-RXL.AX, page-28

You're not wrong NL - it's between 900 and 1000m deep across the deposit.

However if this isn't economic then Admirals bay (MCT) certainly isn't and they are doing a scoping study currently (111mt @ 5.7% Zn Eq for 6.3mt contain metal) as it's a depth of 1315 to 1570m deep across the deposit.

So we should find out soon enough where RXL will sit on the cost curve because it will be half the mining cost of AB due to grade and depth and similarly due to grade have a much cheaper processing capex (double the grade is 'roughly' half the capacity, depending on mineralogy and metallurgy).