“The chlorides are eating it alive,” she muttered, reviewing the X-ray diffraction data. “If we use traditional alkaline washing, the metal will snap. If we do nothing, it powders within five years.”

Elara pointed to the edge. Under the microscope, the inhibitor had preserved the original crystal structure of the steel—the martensitic bands laid down by a Celtiberian blacksmith in 200 BCE. The corrosion was gone, but the history remained.

Elara knew what it was. CM352 was a strange hybrid: a corrosion inhibitor originally developed for reinforced concrete bridges, later adapted for archaeology. It wasn't just a sealant. It was a chelation agent with a specific electrochemical trick—it targeted free chlorides while bonding to the ferrous surface at a molecular level, forming a hydrophobic film only a few nanometers thick.

She didn’t sleep at the lab. She watched.

For the first hour, nothing happened.

Conservation Lab, Museo de Arte Antigua, Valencia Time: 2:00 AM

Elara leaned back. The sword still looked like a wreck. But her handheld resistivity meter told a different story. The corrosion potential had shifted from -650 mV (active corrosion) to +120 mV (passive). The metal was, for the first time in two millennia, quiet .