Pokémon Ruby Tips

Items Galore
If you find Clamperl, he might be holding shards
If you find Bagon, he might hold a dragon scale
Solrock might be holding a sun stone
Cacnea might hold a poison barb
If you find a Snorunt, it can 54.8 percent hold a rare candy, so stock up on Snorunt, (found in Shoal Cave ice room (when the room isn't damp)

You can get blue and yellow shards from Chinchou also. Also I forget whether you can catch Lanturn but I think you can get blue/yellow shards from them.