Hi I found my Grandfather's old Marble woodcraft knife from around 1919. I'm wondering if I should clean it and sharpen it or just leave it alone? I don't want to screw up the value (if it has any). I don't know that much about knives so please let me know what you guys think. Thanks. Also if someone will tell me how to post pics i'll post some pics of the knife and sheath
. Thanks.