Yes, BTC is Spodumene Lithium, as is NMX, HLM...Yes Mouserman, you are absolutely correct, BTC is Spodumene Lithium in Ontario Canada (hard rock, Not brine), similar to NMX in Quebec and HLM also in Ontario. Both NMX & HLM have some of the highest grade "hard rock" Lithium "deposits" of significant tonnage in N.A.
The NMX and HLM Lithium grades are similar to Rio Tinto in Serbia with HLM's average Lithium grade slightly higher (& Zones of interesting tonnage that are nearly double the grade of Rio Tinto Lithium).
Of course, Western Australia is the global leader in hard rock Lithium production.
My understanding is, the Greenbushes Lithium Operations are the largest (51/49 percent owned by China's Tianqi and Albemarle respectively).
A significant Australian hard rock Lithium discovery is Pilbara Minerals (market capitalization ~ $500 million) and very recently, a tiny upstart explorer (MacArthur Minerals) has secured a very large land position (1,200 square kilometres) that is proximate to Pilbara, although MacArthur has a small market cap of ~ $6 million and I am not aware of any reported Lithium grades.
Nonetheless, the Ontario, Quebec and Western Australia hard rock Spodumene projects are quite compelling. Someday, one or two global Lithium conglomerates will likely own most of them, probably Tianqi &/or Albemarle.
You are correct again, NMX has a market capitalization of well over $200 Million and HLM market cap of ~ $30 Million. NMX is well advanced and construction ready, whereas HLM has indicated Pre-Feasibility to begin sometime in 2016 (Environmental Baseline & Metallurgy are well underway according to the March press release).
Yes, the NMX project NPV is $1.9 BILLION & Internal Rate of Return (IRR) is 38%. Quite robust.
Those are a few details I know about, in regards to some key "hard rock" Spodumene Lithium developments.
wirtz.