Question: Do you think that on planets there will be any precious gems like diamonds?

Adam Stevens answered on 14 Mar 2012:

It’s just as likely that they’ll be there as it is on Earth. Precious gems are created by the massive temperatures and pressures that happen under the Earth’s crust, so if a planet formed the same way (and we think that there are other rocky planets in other solar systems) then it’s entirely possible they’ll have gems.

Never know, if might make going to Mars profitable!