The cipher, a crowned, double C, is likely to be of the Heiress Presumptive Caroline (1793-1881). She was a daughter of Frederik VI (1768-1808-39) and was married to the Heir Presumptive Ferdinand (1792-1863), a younger brother to Christian VIII (1786-1839-48).
Four months after her birth, on 26 February 1794, Christiansborg Palace was destroyed by fire. Subsequently Princess Caroline moved with her parents to Amalienborg Palace where she grew up.
Amalienborg is the Danish monarchs winter residence. The Amalienborg complex consists of four palaces, planned around an octagonal courtyard, in the centre of which stands the French sculptor J.F.J. Saly's equestrian statue of Frederik V, the founder of Amalienborg Palace and Frederiksstaden, the surrounding district of Copenhagen.