Hi there dlk52,
We understand that you would like to copy the photo of a contact on your iPhone to the Photos app. We’d like to help however we can.
There would not be a way to do this with your iPhone. If this is something you’d like to do in the future, we encourage you to submit feedback about this here:
Feedback - iPhone
However, if you sync your contacts with iCloud, you can go to the iCloud website on a computer, open the Contacts section and find the contact with the photo you would like to retrieve. Once you find the contact, select ‘Edit’ and you should be able to right click on the photo and save it.
Edit a contact on iCloud.com
Cheers!