Ancient Gold and Coral Bracelet is a treasure in Uncharted 3: Drake's Deception. It can be found in Chapter 13 - Rough Seas. From the green bridge leading to the Pirate's ship head right across the small gap and turn the corner. The bracelet should be laying on the ground.
Approach the winch, but don't ocelperate it just yet. Instead, visit the floating platform to the right of it beforehand to find this Treasure hidden just out of sight.