There is a book (The Big Score) written on this topic, if you are really interested.
http://www.amazon.com/The-Big-Score-Friedland-Voiseys/dp/0385259069
Voisey's Bay Ni/Cu deposit went for $4.3B (SP went from $1 to $161 after many splits). Inco won the battle and later sold (the expanded deposit) it to Vale for $12B.
We are talking about 2 different beasts (Ni/Cu which is sold by the lbs in open market versus graphite sold by the tonnes in niche markets). I would say it's not realistic comparing the 2 situations, using VB as a target price. Currently, ZEN Market Cap is ~$100M, even assuming a x10 it would bring the value to $1B (SP ~$18.5/s) which is far below the values of VB.
In addition, we need to bring in the head guys. It's AE versus the legendary explorer and promoter billionnaire Robert Friedland. With due respect for AE, but there is no way he could match RF.
All that said, I would not be brave enough to forecast any SP above $20/s for ZEN. A $10/s would attract my undevided attention.
$10/s does not look as sensational as $161/s) but it's still x5 of the current SP,... and x30 for those lucky people who got in at ~$0.30/s.
goldhunter