In June 1991, treasure hunters discovered some iron helmets, guns, jars and cannons about 15 feet underwater in the Bahamas.
Archaeologist Corey Malcom realised within moments of seeing the area that the marine salvagers had come upon an important shipwreck from the European colonization of America.
The salvage group from St. Johns Expeditions, usually looking to make a profit, willingly gave up the discovery (a rare move among treasure hunters) to allow Malcom’s team to examine the wreck.
After more than a decade of research (still ongoing), Malcom’s team of divers and conservationists believe the ship is the Santa Clara, a Spanish sailing ship from around 1564.
Thanks to Malcom and the Mel Fisher Maritime Heritage Society and Museum, we have an amazing look at the discovery and restoration of this invaluable treasure.
The vessel was discovered on the southwestern edge of the Little Bahamas Bank, about 23 miles from Grand Bahamas Island.
The first thing the team did was grid the area off into 5-meter units while mapping visible items as well as going over the area with metal detectors and marking any readings.
Each one-square-meter section, coloured-coded by year, was labelled individually. The divers would only see a small portion of the shipwreck at a time so this map helped them tie it all together.
One diver drew (to scale) each artifact found within each unit while the other diver placed tags and bagged the items.
Malcom said that the excavation is only half of the process because once you find the objects, you have to transport them to the lab to know what you're dealing with.
Heavy iron artillery, being moved for the first time in over 400 years, had to be carried to the area beneath the workboat.
Here it's lifted onto the boat by a crane to transport it to the conservation laboratory for testing.
The main body of the ship was very fragile and couldn't be moved, so the team reburied each hull structure they found by pouring sand on them to preserve them in their exact spot.
Once the area is cleared of wreckage, the excavation continues to the bedrock level, where they found a lot of lead.
Members of the conservation lab work to reverse the centuries of physical and chemical changes so that the artifacts can be displayed after being salvaged.
Each item must be kept wet and given a chemical bath along with +/- charges in a electrochemical process that removes the centuries of salt so that over time — sometimes over years — the object will be salt free and stable enough to display.
The sword is broken apart, each part cleaned on the inside, glued back together and hardened (by pouring resin into it that turns into plastic) before the encrustation buildup is carefully chipped away.
The conservation process is so complicated because each material type requires its own specialised treatment; here the sword is being bathed in acid to remove stubborn encrustation.
The sword is given a final brushing of debris, then colorized for final treatment so that it matches with how it originally appeared; some of the wood from the sheath survived.
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