Almost anything equipable can be unravelled - if I remember correctly, about the only restriction is blessed items and items with no magical properties at all (the resist/DI bonus of exceptional items does not count as a property to unraveling).
(the restrictions on what you can imbue with the resources you get are much stricter)
standard disclaimer: everything we've seen is a work in progress, subject to tweaking or outright change over the next two weeks.