Yes. But only regarding another colony farther out in space, say, on Mars. Therefore comes back the original question.

The clearest answer to the economic question I've seen is asteroid mining. A single asteroid can contain orders of magnitude more platinum than has been mined in all of human history, in a very concentrated form. Which would obviously crash the market for platinum, and could encourage interesting new uses for it when it's no longer ~$1,000 per ounce.

How is that a clear answer? You're still shipping massive amounts of rock through outer space. If it costs you $100M/oz to mine and transport the stuff, then selling it for $1000/oz doesn't even make a dent. And crashing the market doing it is just lose-lose.

Everything is economically viable when you can employ fantasy magic technology to make it happen.

Why would it cost that much to transport it? You've got lots of gravitational potential energy to work with, in terms of shipping down to Earth, so it doesn't take the kinds of fuel that it takes to ship things out of the Earth gravity well. And you don't need to bring back the whole asteroid, just the products, so you're not shipping "massive amounts of rock through outer space".

Are you familiar with the companies that are being set up to do this, and that are backed by Eric Schmidt et al?