Watch List notes:

(g) PF70 ULTRA CAMEO | Elizabeth II (1952-), Proof Sovereign, 1998, fourth head, edge milled, 8.00g, 11h (Spink SC4 [4430]), brilliant uncirculated, in Royal Mint case of issue, with Certificate of Authenticity, no. 7925, in NGC holder, graded PF70 ULTRA CAMEO (Cert. #6295122-004).
Provenance
The Lansdown Collection of Guineas and Sovereigns,
Estimate: £350 - £450