"Why would Noront have taken on a debt equivalent to more than a third of their market cap, to buy chromite claims, if the chromite is not likely to be economical for a long time?"

Because they think in the long term and it was one hell of a good deal. Besides there was more than just chromite on the Cliff's claims there was also nickel, copper, pgms and possibly diamonds.

You also forget that Boa Steel is already a major share holder in Noront and they had plenty of opportunity to invest in chromite but didn't put up one penny for the Cliff's claims. These are all Chinese government controlled companies so you can be sure they know each other's business. Yes they have an interest in the ROF minerals but not in the near term. Their only near term interest is to get some business building a railroad at our expense.