Watch List notes:

(g) George V (1910-1936), Proof Sovereign, 1911, by Mackennal and Pistrucci, bare head left, rev. St George and Dragon, edge milled, 8.00g, 12h (W&R 416; Marsh 213A; Spink 3996), some surface friction in otherwise brilliant fields, extremely fine.
Provenance
The Apollo Collection
, ,
, NGC PROOF DETAILS ~ Obverse Cleaned (Certification #5880295-003)
, https://www.ngccoin.com/certlookup/5880295-003/NGCDetails/
Estimate: £600 - £800