Got a brief look at Norske Solvstemplar by Jorunn Forsberg today. Can confirm the pictorial mark as Oslo/Christiana/Kristiana, no specific dates, but used in the 19th cent. Crowned "C" was used earlier.
The "C" on this piece is the assay or guardian stamp for H. Clausen (1824-46)
The "FB" is the maker's mark for Fredrik Julius Brinck (b. 1808 - d.1867)
He was active after his apprenticeship from 1833 to 1857.
Lacking a Norwegian translator, the date info is correct, but what they refer to may be somewhat off.