Artifact Stabilization
When a wooden ship rises from the dark seabed, the wood begins to rot almost instantly. This rapid decay happens because the salt inside the wood creates a chemical imbalance once the object hits the air. You must act quickly to save these fragile treasures from total destruction before they disappear forever.
The Science of Salt Removal
Removing salt is the most vital step in keeping an artifact stable for future study. When objects stay underwater for long periods, salt crystals fill the empty spaces inside the material. If you let these crystals dry out, they expand and break the object apart from the inside. Think of this like a frozen pipe in winter where expanding ice cracks the metal. You must soak the object in fresh water to pull the salt out slowly. This process is called desalination and requires patience because rushing can cause the structure to collapse under stress. By changing the water in the tank regularly, you keep the concentration of salt low. This ensures that salt continues to move out of the object until the levels are safe for display.
Key term: Desalination — the process of removing accumulated salt from an artifact to prevent structural damage during the drying phase.
Protecting Fragile Material Structures
After the salt is gone, the object needs a way to hold its shape while it dries. Many waterlogged items rely on the water inside them to keep their form intact. If the water evaporates too fast, the surface tension pulls the cell walls together and causes the item to shrink or warp. To prevent this, experts use a chemical called polyethylene glycol to replace the water. This substance acts like a support beam for the tiny structures inside the wood or leather. It fills the gaps and stays solid once the water is removed. This method keeps the artifact looking exactly as it did when it was first found on the ocean floor.
Conservation experts follow a specific sequence to ensure the best results for every item they recover:
- Initial cleaning removes loose mud and debris to expose the surface for chemical treatment.
- Long-term soaking in treated water tanks helps pull deep salts out of the porous materials.
- Gradual chemical infusion replaces water with a wax-like substance to provide internal structural support.
- Controlled drying environments prevent sudden temperature shifts that might crack the surface of the item.
This sequence ensures that delicate items do not shatter during the transition from wet to dry environments.
| Material | Primary Risk | Treatment Method |
|---|---|---|
| Wood | Shrinkage | Wax infusion |
| Metal | Corrosion | Electrolysis |
| Leather | Brittleness | Oil treatment |
Each material requires a unique approach because the chemical reactions differ based on the composition of the artifact. For instance, metal objects often need an electrical current to pull out harmful chloride ions. This electrical cleaning process is quite different from the soaking method used for organic materials like wood. By tailoring the treatment to the specific needs of the object, historians can preserve items that would otherwise turn to dust. Each step requires careful monitoring to ensure the artifact remains stable throughout the entire process.
Stabilization turns fragile, waterlogged items into permanent historical records by replacing corrosive salts with protective chemical supports.
Since the artifact is now physically stable, how do we record its exact location and history to ensure the data remains as preserved as the object itself?