Actually in my personal view, this is a most exciting item, and for myself and Cap'n Mark , it truly does add dimension to the favorite maritime topics especially the Pirates! While not a weapon itself....these and thier contents were certainly the focus of attention bringing the USE of weapons!!!
These chests are extremely desirable today for collectors, and I always find the lore around pirates and buried treasure most entertaining.
Despite fanciful Victorian notions, there are few accounts of any 'treasure' ever buried by pirates except an established instance by Capt. William Kidd I believe in N.Y. That was recovered at the time though...despite the many tales of his, Blackbeards and many other treasures all over.
As I have understood, most of these 'armada chests' (actually they were called 'strong boxes', the armada chest term again Victorian) seem to have been produced almost invariably in Germany, usually Nuremberg or Ausberg, and late 16th through 17th c.
These often varied in size, but the smaller ones for jewelry were 'caskets' if I recall. As noted this one is nearly 100 pounds empty....which when one imagines it filled with gold (very heavy) makes the gross weight formidable at best. Imagine a couple of pirates tramping through the sand carrying this full of gold!!!
The often illustrated known hump back chest in familiar pirate oriented artwork was actually for travel/clothing etc. and appeared in the 19th c. I believe.
The only known 'treasure chest' with known provenance to a 'pirate' belonged to Thomas Tew (died 1695) and was not dug up, but acquired from his family after his death. It is displayed in St. Augustine, Florida and is one of this 'armada' type with metal straps.