Isla Perdida

From Pirates of the Caribbean Online Wiki

Isla Perdida is home to many Giant Crabs, Dire Wasps and Terror Wasps, hence the part of the Island called "Queen's Nest." Scary Mary can be found here through the right-hand jungle entrance.

One of your quests requires you to find a diamond in the jungles of Isla Perdida. It is in the center of the "Queen's Nest" and you will have to fight at least a few of each type of wasp to find the spot. (There are 2 dig spots on the island, but the one near the hive seems to be the one I've found the diamond at). Be sure to carry healing potions with you.

You might want to have a high level, the beasts (no, not beast mode) are hard and so are the Dire wasps.

way to the right of the water fall, there is a tree with a mark that looks like a wishbone on a tree root, turn right and go behind this tree, past 2 trees making an entrance and you will see two hives. Somewhere between the hives and the two trees you just passed is a treasure spot.

Other dig spot near the waterfalls which is at about 61% of the pearl quests. Its location is just west of the rock bridge near the light colored rock.