The Cauldron of Clyddno Eiddyn

Britain's greatest treasure, the Cauldron disappears 500 years before this novel takes place, and the Druid Merlin's purpose in life is to collect the treasures and restore Britain to its rightful Gods. Arthur doubts that the Cauldron survives the Roman occupation and cannot spare men to search. Wider in diameter than a man's outstretched arms and as deep as the blade of a hunting knife, the Cauldron is made of silver and gold. It has three golden hoops at the rim for hanging over a fire. Warriors, Gods, and deer are used for decoration. It is buried and hidden by the last three surviving Druids when the Romans take the island. Merlin is nearly dead when his companions find the Cauldron and lay him in it, covered with skins, but it restores him.

Later, the Cauldron is stolen when vandals burn down Merlin's center...