ULTRASONIC CLEANING: Target Coins and Findings with the Metal Detector

Today we are doing my first test with the ultrasound tank, cleaning the coins and other objects found during the search with the metal detector, and magnetic fishing.
Ultrasonic cleaning uses a phenomenon called cavitation.
Cavitation occurs when high-frequency sound waves are introduced into a liquid body causing millions of tiny bubbles to form. When these bubbles expand
and they contract, reach a certain threshold and collapse.
This collapse generates a high temperature, at a microscopic point, with a high-velocity jet stream, used to eliminate contaminants from the surface of the object to be cleaned.
Regardless of the frequency used, the acoustic energy must be high enough to reach the threshold necessary to create the cavitation phenomenon.