Each of these increase the difficulty of the action, but also increase the chances of finding uncommon item fragments, with the higher difficulties providing the most unique items.
When finding a fragment, you may get a message in the event tab stating information on past settlement locations. The higher your skill level in Archaeology, the more information you may receive. You also need an Archaeology journal and 30+ ql paperto record records of the deed to get the Cache.
To investigate a tile, activate a [[trowel]], right-click a tile and click ''Investigate''. This will search the tile for fragments.