Ultrasonic and roman coins!

[downindixie]

I have some roman coins that the legend is difficult to read due to the substance in between the letters.Does anybody have experience with ultrasonic and roman coins?

 

[U.K. Brian]

No problems with ultrasonic but could be if you add a cleaner to the water. I find a drop of soap solution does help but use a car cleaning product as it won't have the salt that washing up liquids contain.