I am no expert by any means but just from looking at your pictures I would say those cards are awful white for being over 100 yrs. old. Paper will show fading or yellowing long before 100 years. I would try and get them authenticated before you made any attempt to sell them.
Looking for framed Gridiron Kings cards..all colors...
Looking for Gridiron Kings Prime Patches..Multi color only....
Ray27Ray52 is my Internet squeeze toy