[@Loony]

yeah, that is what I am trying to figure out...it would be hard for a human to know anything big about gems. The only reason Greg knew everything or more than others is because Rose told him. 

The only reason I thought the temple idea is from that one episode that depicted the past war which gave us a little bit of information so I figured it could work the same. It is just that most of it all would be speculation and forming ideas of what it all might mean. The character could have guessed some correct while other the character would probably be really wrong.