BHM 2604 for reverse.
51x41mm. White metal. By T. Ottley.
Reverse with a view of the exhibition buildings within beaded border, obverse with 14 line legend explaining that this medal was struck to commemorate the visit of The Royal Family, along with HRH Prince Frederick William of Prussia, ot the Exhibition of Art Treasures.
Nearly Extremely Fine and very rare. A similar medal with this reverse but with the obverse featuring a bust of Prince Albert is listed in BHM in bronze as RRR but is unlisted in white metal. This medal is seemingly unlisted and so presumably even rarer.