A pierced pendant I made, has recently become tarnished on the inside
of the backplate. The Mexican agate is translucent so the piercing
can be seen from the front. In trying to remove the tarnish I have
used my ultrasonic cleaner ( to no avail) and the aluminum plate with
the washing soda and heated water. Neither of those processes worked.
The tarnish still remains. Is there any way of removing the tarnish
short of removing the stone and redoing the entire setting...
backplate piercing, bezel and bail?
Diane in Long Beach, CA