What you see is one of the ways to hide a pointer to an opaque C structure in a Perl object returned to the library user. (Use Dump on an Image::Magick object to see a different one.) As others have already pointed out, recreating these objects from such dumps is probably a bad idea because the pointer that's stored somewhere is no longer valid (or, if it is, destroying the recreated object will also free the memory belonging to the original).

See http://gtk2-perl.sourceforge.net/doc/binding_howto.pod.html for more information on how it is achieved and perlxstut for more information about the language used to extend Perl with code written in C.