In nethack, how can you tell the difference between a gem and a worthless piece of glass? Also, besides selling for lots of money, what are gems good for?

Roguelike games are characterized by (usually) text based ASCII graphics, random maps and (often) combinable in-game items. Most tend to follow traditional fantasy themes, though s …

The Trident of the Red Rooster is required to complete any of the "ultra endings" in Ancient Domains of Mystery. I've never been able to acquire it (and so always end up finishing …