You can catch all the unown, after solving the puzzle in a small cavern on island 7, you can work on your pokedex, fight in the trainer tower (also on island 7) um other than that, not too sure what else (assuming you've caught the legendary birds, mewtwo, and the legendary dog of your game)
Not really. Sell them, or give them to Pokemon to hold.
After you have obtained both the Ruby and Sapphire gems, you should go back to One Island so Celio can fix the machine he's been working on. By returning the two gems, trade with the Hoenn region is unlocked (ie. you are now able to trade between your version and Pokemon Ruby, Sapphire and Emerald). The two gems do not unlock anything else, but clear a significant obstacle which prevents you from completing part of your National Pokedex.
She is in the Indigo Plateau where the rest of the Elite Four is.
you have to beat the elite 4 and N then you go to the beach city and go inside the mansion but before you go inside you have to battle a boy when you are inside go to the boys dad and then you can sell it (ps) i think it will work with big nuggets i hope this helps
With the dotted holes in leaf green, that is where you get one of the gems to get inside the Rocket Warehouse. Just have a Pokemon that knows cut, go up to it, then press START, POKEMON, ???, CUT. It's that easy!
the underground
The only way of getting gems is by you buying on the top screen where it shows you how many gems you have.
you must catch 60 Pokemon
Gems weren't made yet but they didn't hide the bar
You get five gems for first place.
by going to that site and clicking getting started on the left.
I think you get gems by playing Sableye's Gem Journey
Not really. Sell them, or give them to Pokemon to hold.
You can get free gems from in the game. Clearing rocks, trees, stumps, and mushrooms are all ways of getting some gems.
No You don't.
swirly dust in caves.
you go to the elite four which is to the left of the place you got your 8th badge. you need to cut the tree then go through a cave to get there. it'd be a good idea to have Pokemon with levels over 60!