The main question in deciding which minor to open is whether you want to rebid NT or not. If you aren’t going to rebid NT, say because you have a small singleton then you should probably open 1D. You won’t love rebidding 2C but it may be the best of bad alternatives.
OK, suppose that you’re balanced, which minor should you open? 1C has the advantage that it allows partner to respond 1D with a hand that doesn’t want to be the NT declarer. There’s another guideline that I didn’t invent but I don’t remember to whom to give credit. If you’re in the 12-14 range there is a tangible chance that the opponents will buy the contract, so you should bid the minor you want your partner to lead. On the other hand, if you’re in the 18-19 range then your side is going to be playing it. In this case you should open the weaker minor, ala Victor Mollo’s Hideous Hog. It’s just a thought.