It could just be that initial drill holes turned up little mineralization of value and more work is required to identify a deposit. Noront was extremely lucky with there drilling which doesn't happen often.

It's far from unusual to drill a number of holes before hitting what one is looking for. Anyone who thinks it's easy finding deposits like Noront has is dreaming.

There will be additional economic metals found and no reason why one larger and possibly richer than Noronts won't be found. Management don't have to report dud holes so will wait until they get a few that show something before releasing. Mind you the fast run up makes you wonder if they haven't already found something to follow up on.