Gearld chest

[Diego Birmingham]

Remember also that if your dig is interrupted you have to start again to find anything there.

I think the spot you are looking for might be the one "behind" the town.

[Calico Jack Rackham]

I am having the same issue. I know of 5 or 6 places to dig on Tortuga, and all of them come up "Nothing of Interest Here".... I finally got frustrated and decided to do something else. I did not check for any dig spots in the interior zones, just the main dock/city zone. I wonder if the "He died in a pretty nasty place" comment means I should check somewhere more dangerous... Dunno. My guild mate told me he found it by the pig pen.