The Broken Claymore is treasure that can be obtained in Sly Cooper: Age of Thieves in the episode Braverobbor. It is worth 238 coins, and the time that is needed to get this treasure to the safehouse is twenty-nine seconds.
"This claymore was said to have been wielded by Slaigh's mortal foe, The Dark Duke of the Loch. Slaigh has cherished the memory of saving Scotland from that fiend, and the gemstone in the hilt adds value to this already valuable treasure."
It is located behind a door that can only be opened if enough electricity short-circuits the lock. Carmelita is the only character who can access this treasure.