Need help with identifying initials

I have a ring bought in a lot of native jewelry . it is signed with script initials FMB. ANYONE EVER SEEN THIS?

Scripted initials can be very difficult to identify. Also, it would help if you provided a picture of the top, to determine what style the ring is Navajo, Zuni, Hopi etc… I did look through the reference books we use and did not come across this mark. Thanks for sharing.