Did anyone else see the email the other day from The Holy Black that the map included with The Galleon soap is part of a bigger treasure hunt?

I checked a couple things, but didn't have much luck. The map has a square on it, so my initial thought was that it overlays something and whatever is in the box is a clue. I checked around Lindenhurst (their location) and the Mexico mint but nothing matched up. Also tried to find any unique locations related to the boat, but didn't find much.

Anyone else have any ideas? Here is my piece (bottom left part)

edit 1: We have 3 map pieces as of now. Thanks /u/TheManWhoDoneIt /u/thenewloser and /u/Nocturnx . Need top left still if anyone has it. Notable items on map include THB logo, a compass rose, an X, a lion emblem (possibly relating to the spanish coat of arms), and a rectangle

edit 2: /u/bobbydixonpr has the 4th piece. Woot! /u/Nocturnx noticed that Hart Island has a lot of similarities to the map, although not exact

edit 3: full map - thanks /u/Nocturnx and /u/ACMEanvils

edit 4: /u/theholyblack has mentioned something about a library and says shovels are required. There seems to be 3 major symbols on the map. The Holy Blacks THB logo, A lion emblem likely related to the Spanish crest, and some sort of hat/bag/horn thing that may or may not look like a face.

edit 5: Looks like we need Brotherhood access. /u/TheManWhoDoneIt can look. If anyone else has access, take a peek. I don't have Instagram :(

edit 6: /u/Nocturnx found a note written in French on the brotherhood page that has some hints

Edit 7: /u/Nocturnx made the trip to New York last night and got to Knollwood Estate this morning. Took a bit of poking around but he found a Piece of Eight! We are patiently awaiting pictures!

Edit 8: Treasure Pictures! A replica doubloon from Goonies!

Final edit: Recap of the treasure hunt for those interested