The legendary mace Val'anyr, Gavel of Ancient Kings will be introduced with patch 3.1.
It will be assembled from 30 Fragments of Val'anyr. These fragments are BoP and will most likey drop from raid bossed in Ulduar. Combining these fragments will construct a Shattered Fragment of Val'anyr which will start a quest to obtain the mace.

Stats from the WoW-Armory

Val'anyr, Hammer of Ancient Kings

Binds when picked up
Main Hand Mace
93-298 Dmg
(108.8 damage per second) Speed 1.80
+52 Stamina
+54 Intellect
Durability 125
Requires Level 80
Equip: Improves critical strike rating by 47
Equip: Improves haste rating by 46
Equip: Increases spell power by 587
Equip: Your healing spells have a chance to cause Blessing of Ancient Kings for 15 seconds allowing your heals to shield the target absorbing damage equal to 15% of the amount healed.
"The power of creation courses through this weapon."