What's the name of this effect?

[Randy]

It's one I saw David Blaine do a few years back and also saw Criss Angel do when his show was half way decent.

It's where you take a person's watch or cell phone and then proceed to destroy it and then end up magically putting it together.

 

[dansperry]

there are a lot of different versions of this where an object like that is destroyed - vanishes - and reappears sealed in something like a can of ::insert favorite food here::

One of the more popular ones is Relativity by collector's workshop, similar ideas are Joe Givan's ring in gumball machine, and even for kid shows steve hart's wiz kote or the owen redwine burned shoe version...