Try out this article. A good number of things we've heard before but it discusses the Graphite market and puts a perspective on it that could indicate why ZEN isn't attracting much attention and why investors may not venture there as there are too many unknowns and it's too difficult to preduct what profits could be or even demands. As has been said it's a very closed market and a lot harder to make a go of than most think. Having said that, ZEN demonstrates the characteristics to succeed is success is possible.

http://www.theenergyreport.com/pub/na/flinders-ceo-blair-way-what-tesla-needs-to-know-about-the-graphite-sector