Ignace Pleyel Unicorde
Marked: Unicorde Par Brevet D'invention Chez Pleyel & Cie Paris
This is a very rare find! There is possibly only 20 of these known to have been made, and only four including this one are known to exist today! Square Pianoforte Unicorde made by Ignace Pleyel serial number 955 year 1828.