Brazil and some other countries would re-strike their coin design over another countries' silver coins. I'm talking about the whole coin being covered where you don't see any of the original host coin's features What's the name/term for those coins ?
Overstruck coins can be quite interesting to collect. Some common countries come to mind - Russia, Sweden, Italy Here's a list of world overstruck coins that I have collected. http://gxseries.com/numis/overstrike/world_overstrike.htm It can get quite addictive.
When the entire host coin is covered up, it is called an overstrike. When much of the host remains visible, but the reissuing authority just puts a small mark (an eagle, a bust of the king, some words, etc), that is called a counterstrike. A counterstrike is from an official government authority, as compared to a chopmark which is a private banker's mark.