That depends. If Emeralds take time to mine, then it's likely that people will be willing to pay money for them (like people usually are with all other items that take time to make).

But setting a peg between Emeralds and bitcoins won't work, it will have to depend on people voluntarily trading in the game. For every bitcoin you get out, someone else must have put one in.

Yes, you can. We also made emeralds easier to find in this first stage so we have lots of them flowing inside the world.

Emeralds are also good for buying stuff other people craft, tipping other players and entering tournaments, and we are working on more ways to use them. We have found most players don't cash out and use it to have fun

Who said Bitcoin wasn't real-world money...