I like the phased approach of starting with spodumene concentrate and progressing methodically over to lithium carbonate.
Reduce the time to money, take advantage of the current high price environment for concentrate and utilize cash flow to help fund the chem plant, reducing dilution as much as possible.
Another company I follow CRE is taking this exact approach, and I've shared this on here before.
The above project is in the final stages of completing a bankable feasibility study for phase 1. And if you're wondering if you're reading that correctly, that's right, phase 2 isn't set for production until 2022... For anyone who thinks that putting together a chem plant to produce high quality battery grade lithium carbonate is easy peasy, you're dreaming... At that stage, we aren't talking much about mining at all anymore, but a straight up science/chemistry project... This is when you need to start planning on hiring a bunch of: ALB, SQM, FMC guys on your staff... Or ex-Rockwood chem engineers as CRE did.
And to bring in a whale of a partner (chem expert) to make sure it's done right, which could still easily take a few years.
Anyway, the timing should coincide quite nicely with the rail upgrades.
But if you're already cash flowing nicely via phase 1, what's the rush?