Great read about EMH, page-37

yep, you got it wrong.

LPD:
$350/t
29,000t
for
3,000t Li2CO3
=$3,383/t of lithium carbonate.

for EMH, straight out of Table 5, cost of concentrate is:
Mining $1,960
Plus FECAB $935
Minus Sn/W -$1,404
= $1,401/t of lithium carbonate.

So EMH should make almost $2,000/t more than LPD if they used L-Max per tonne of Li2CO3 not accounting for economies of scale. The grade issue is roughly six of one and half a dozen of the other when it comes to head grade Vs byproducts. Zinnwaldite can be considered roughly equivalent to Lepidolite. And there should be more tantalite in the zinnwaldite since it's a mag sep to produce it.