So:
@ $20k, the share price could be 280/273 = $1.02.
@ $30k, the share price could be 630/273 = $2.30.
@ $40k, the share price could be 980/273 = $3.58.
Of course, the share price represents CSD's value but with risk factors applied (which sometimes are completely wrong).
If tin hits $40k, my target price would be 50% (if the JV is occuring) of $3.58 plus the 10% 'free' carry value (plus the option money), then multiplied by my perceived risk value.
I can assure you, with a tin price of $40k/t, the value I get is way more than 40 cents!''