Take a look at this old RR luggage tag.  L&N RR and SF&W Ry P2172 via P&A RR.  After some Googling, I have L&N RR and South Florida and Western (absorbed by L&N) then the ID number, then via Pensacola & Atlantic RR.  Does anyone have more knowledge of these pieces?  Best I can tell it is brass. Some were pewter.  My neighbor found it in 8 inches of soil just off the old track at Browning Springs Middle School, Madisonville, Ky.  Lucky me! – Bill Thomas