Yes, where you battle Dialga, once you catch it or defeated it, go in the back of Spear Pillar and there will be a Pokeball Container containing Adamant Orb.
In Pearl, the Adament Orb, meant only for Dialga, can only be obtained through trading from Diamond or another game.
The adament orb in platinum is in mt. Coronet
There's A Room In Mt.Coronet That Has The Adamant Orb And The Lustrous Orb.
it is an item that dialga holds when you catch it
in mt. coronet,use waterfall in an part of it,go it the room to get the orb and the lustrous orb
you find the adament orb in the cave near the to of mt.coronet
Yes, all you need to do is bring either a Lustrious Orbor Adament Orb to Spear Pillar (where you find Giratina the first time, and also where you see Palkia/Dialga in Pearl/Diamond). Whichever orb you bring to the Pillar will effect the Pokemon that appears there. (Lustrious = Palkia | Adament = Dialga)
Let Palkia hold the lustrous orb, and let Dialga hold the adament orb. It boosts their special moves' damage.
I dont think you can even though you get the adament orb,the lustrous orb,and the griseous orb from the shadow triad on marvelous bridge.
mt coronet use waterfall to find the room it is in
Answer TBA Soon... Pokemon Vortex Help
TradingYou can't get an Adament Orb in Pearl. If Nintendo made it possible, then you would have one less reason to trade with a friend. Trading exists to encourage purchasing more than one of Nintendo's products.