One of the many commendations you can complete as you bury and dig up treasure is the Seeker of Pirate Plunder commendation.
To complete this commendation, you must uncover valuable treasures buried by other pirate crews. You will need to uncover a total of 25 treasures to complete the commendation fully.
To work on this, you will first need to get your hands on some Treasure Maps.
Seeker of Pirate Plunder Commendation
To complete this commendation, you will first need some Buried Treasure Stash maps created by other pirate crews. The Treasure Stash maps will lead you to treasures buried by other pirate crews.
You can collect other pirate crew’s Buried Treasure Stash maps from the Quest Board found on the dock at any Outpost or Seapost. You can also acquire them by stealing Map Bundles from pirate ships!
Though, it’s much easier to find other pirate crew treasure by grabbing Treasure Stash maps from the Quest Board.
Interact with the Quest Board and take the maps most convenient for you. Maps with the word “Hoard” in the title will have more treasure to dig up than maps with the word “Stash” in them.

Once you have another pirate crew’s Treasure Stash map in hand, sail to the island where the treasure is buried and dig at the Xs.
Once you dig up a piece of treasure from the Treasure Map, you will make progress towards the Seeker of Pirate Plunder commendation. You will need to dig up a total of 25 pieces of different treasures buried by other pirates. You don’t have to dig up all 25 in one session.