Zanzibar Scott 18-20 Gibbons 23-25 Used Set of Stamps (1)

18-20 (23-25) 1896 2½a on 1a plum Q Victoria stamp of India with "Zanzibar" overprint surcharged in black, Stanley Gibbons surcharges Type 3-5 (Scott Type a-c) cplt, undercatalogued as SG 24 (Scott 19) only occurs 10 times in the setting of 60.