When clicking the link it goes to the details in the online Royal Collection, and says -
A posthumous copy by Schäfer after a portrait by Conrad l’Allemand known from a lithograph by Fr. Jentzen published by L. Sachse & Co., Berlin. On the basis of costume, the original (current location unknown) can be dated to c.1838, when the distinctive ‘Victoria’ sleeves with bouffants on the upper arm were fashionable. The Queen of Hanover wears with her purple evening dress the badge of the Order of Louise of Prussia and George IV’s family order. Signed in pencil on the reverse: A. Schäfer p. / 1846 and inscribed No. 4
--Previous Message-- : Apart from the Prussian Order of Luise, which : Royal Family Order is Queen Friderike of : Hanover wearing? : : Thanks in advance for these fabulous : portraits & photos.