Benjamin Franklin 1¢ Stamps

I've acquired these over the past few years and I have a lot more 1¢ & 2¢- stamps on the postcards in my collection I've researched a lot online for their value and find it a difficult task because they look so much alike but only a few are worth more than their 1 or 2 cents. I'll be posting a few more. Hikes!! I welcome assistance.