I was looking into this due to El Jefe's post and wondering if...

I was looking into this due to El Jefe's post and wondering if it was more a lack of understanding or knowledge (every chance of both haha...) on my part as the expected recoveries isn't exactly stated clearly but can be worked out to a range from the mining schedule numbers.

Reading back over the SS today I come across this at the bottom of page 12 -
'The feed to the concentrator is expected to be high grade, thus the recovery of the separate galena and sphalerite ore is expected to be similar to current high grade concentrates received by the smelters averaging in excess of 95%.'

So based on this I'm assuming close to 95% is the assumption which basically matches your calcs.



Interestingly toward the bottom of page 9 of the SS-
'An economic cutfoff grade (COG) was estimated based on the product price, transport costs and treatment charges (TC) available at the time of optimisation (as at April 2018). The COG was estimated to be 5.8%Zn or 7.6%Pb or 10% of the mixed ore.'

Considering that was based on a Zinc price of $3200/t (currently around $2600/t), everything else being the same this number would have risen. From this ann they clearly believe processing 8% head grade Zn ore is profitable currently. That would imply that further work has gone into mets/processing and that they believe lower grade material is still able to be processed and it would be likely that significantly lower than 8% Zn ore is profitable currently.

If this is the case, any increase in Zn price would have a compound effect on the economics here.