All About Pocket Knives

I think this belonged to my father who died in 1959. Can anyone tell me how old it might be and if it can be cleaned around the tangs(hinges).
It look as if the scales are bone or ivory

Geo. Butler & Co., Trinity Works, Cavendish, Sheffield. 1768-modern day. The "ART" stamp began in 1861. (Ref. Levine's Guide 3rd Edition) Can't tell from your pics if its white bone, ivory, or celluloid. Value??? It's a bit worn out. Nice keepsake from your Dad. J.O'.

For cleaning, from the looks of the knife, I’d try the graphite (lead) end of a pencil. Just rub the pencil lead onto the tang, wipe off with a soft cotton rag. Don’t worry about rubbing too hard - the lead/graphite is a very soft abrasive, softer than the steel but harder than the tarnish. It will remove tarnish (and light rust) without damaging the blade or the stamp. Hint - if you have a carpenter’s pencil use it. Those have a thicker, wider lead so you won’t have to resharpened it as often and you can rub harder. Don’t forget to put a drop of oil into the joints when you finish.

Show us some before and after pictures!

Ken

Thanks for the replies, it’s all very useful information.