The HA is most likely the maker's mark, which would be Adkin Brother - Harry Adkin.
Antique Victorian Silver Plated Nautilus Shell Spoon Warmer - circa 1890
Good Engraved Antique Victorian Silver Plated Nautilus Shell Spoon Warmer
Gorgeous Antique Silver Plated Nautilus Shell Spoon Warmer – circa 1860
Antique silver plated nautilus shell spoon warmer
Late Victorian Sugar Shell Spoon Rd 265922 Art Nouveau Design
Antique Silver Plated Spoon Warmer in the Shape of a Nautilus Shell, Atkin Bros
