Copper bonds GREAT to rock and quite poorly to glass and silicone. It takes a ton to get glass and silicone filled with copper.
In terms of copper removal from the rock work...well, good luck. Most people end up deciding to just pitch all the rock and start all over.
However...there is a product called Cuprisorb made by Seachem. They report that it removes copper. Supposedly can be regenerated. Basically, you'll have to run it on your tank for the entire length of the tank's life as long as you have the pieces of rock you treated...which is why we normally use pieces of PVC
for fish to hide in/around when we QT and treat with copper.
Here is a link: Seachem. CupriSorb