Watch List notes:

GERMANY. Mainz. 1/8 Taler, 1729-BIB. Lothar Franz, Freiherr von Schonborn. PCGS MS-63.
KM-251. A sharply struck and softly lustrous coin, issued upon the death of Lothar Franz, with pleasing dark toning throughout.

PCGS has called this a 3 Kreuzer on the holder. However, the 3 Kreuzer has a "3" within a globe on the reverse at about 6 o'clock and a smaller legend, neither of which this issue has. This confusion likely stems from the image presented in the Standard Catalog for the 3 Kreuzer, which erroneously displays this type instead. The 1/8 Taler-the denomination here-is a slightly larger module weighing ~3.2 gms, while the 3 Kreuzer is somewhat smaller and weighs ~1.9 gms.

Estimate: $200 - $400