Watch List notes:

BRITISH COINS, George V, Gold Sovereign, 1921 S, Sydney mint (Australia), bare head left, B.M. on truncation, rev St George slaying dragon with sword, S mintmark on ground, date in exergue, tiny B.P. to upper right, 7.98g (Bentley 737; McD 267; QM 199 S; KM 29; Fr 38; Marsh 281 R3; S 4003). Some light bagmarks and nicks, a little friction on date, otherwise extremely fine and very rare.
Calendar year mintage 839,000. The prevailing gold price c.1920-1924 kept the mintages of Sovereigns low in Australia.

Estimate: £1000-1200