Hiya, i have a piece of reclaimed slate tile of an old house (1800's, house that is) tile is at least 40 years old, Question is :-) i'd like to make something with it, say a pendant, do you think the slate would be ok to use and what would be the best thing to seal it with, wouldn't want to cause anyone an itchy rash

Off to watch a film but will be back tonight just incase there's anyone around that can advise me, thanking you muchly :-)