Thieves Find $500M Treasure in Derelict Mansion Aristocrat though home's shabby state would deter thieves By Rob Quinn, Newser Staff Posted Mar 26, 2010 8:11 AM CDT 7 comments Comments This photo released by the Spanish police shows recovered antique jewels and other valuables recovered after being stolen from Grau-Pla's mansion. (AP Photo/Spanish Police) (Newser) – Spanish aristocrat Jaume Grau-Pla's cunning strategy of hiding the family treasure in a derelict mansion he thought thieves would overlook didn't work. Loot worth an estimated $500 million, including jewels and relics dating back to the 12th century, was stolen from the Catalonia mansion by thieves tipped off by a part-time gardener who peeked through the windows, the Guardian reports. Police have arrested two men and recovered around 85% of the treasure, which Grau-Pla, the descendant of a medieval baron, kept in glass display cases on plain view inside the scruffy building. "I keep the house run-down on purpose as a way to camouflage the high-value collection I keep inside," Grau-Pla explained to the Spanish press.