Too lazy to actually hit reply, but
Jibaku there are actually 4 Meteorites from the
bank datamining 
In order they are:
- Meteorite - A Meteorite originally found at Meteor Falls. You got it at Mt. Chimney.
- Meteorite - A Meteorite that you got at Mt. Chimney. It gives off a faint glow.
- Meteorite - A Meteorite that you got at Mt. Chimney. It continues to give off a faint glow and is slightly warm to the touch.
- Meteorite - A Meteorite that you got at Mt. Chimney. Some sort of pattern has risen to the surface, and it’s shining with seven colors
I'm guessing the first is either scrapped or for Deoxys changing, while the other 3 are various stages of "Rayquazanite" like you said.
R_N this is the "Mega Cuff"

, as far as I can tell it's just the mega thingy for the male trainer's Contest outfit
http://www.serebii.net/omegarubyalphasapphire/cosplay5.jpg (probably scrapped since I don't see one for the female's contest outfit).
Also:
- Mega Bracelet - This cuff contains an untold power that somehow enables Pokémon carrying a Mega Stone to Mega Evolve in battle.
- Mega Cuff - This bracelet contains an untold power that somehow enables Pokémon carrying a Mega Stone to Mega Evolve in battle.
Why do the descriptions not match up? WHY!?