Originally Posted by robhupf
MoorMaps already has this built in.
As Robhupf said, MoorMap already shows Treasure Cache locations prior to Mordor. The next release will also have Rare Treasure chests as well as the Mordor pages. I finally got time to start capturing the annotations so it should be out in a week or two. FWIW, TerrainMap also shows these default annotations (their data files come from the same database).