Watch List notes:

The Lost Collection of Simon English Esq. | Commonwealth (1649-1660), Double-Crown or Half-Unite, 1651, • THE COMMMONWEALTH OF ENGLAND • [sic], English shield within palm and laurel wreath, rev. • 1651 • GOD • WITH • VS, conjoined shields of England and Ireland, 4.42g [68.4grns], 2h, m.m. sun [on obverse only] (Manville & Gaspar, 1991, pp. 137; Ryan 551 this coin; Vaughan-Morgan 150 = Lockett 4245 = Schneider II, 350 same obverse; Hird V, 31 same obverse die; EGC 38/37 [R5]; North 2717; Spink 3210), some unfortunate pin scratches across English and Irish shields, otherwise beautifully toned on a neat round flan, the strike redolent of the recently-offered Hird coin, but a different reverse die with resunk larger letter forms over smaller types in 'WITH VS', the fabled 3Ms error exceedingly clear, almost extremely fine, extremely rare thus, and only the fourth specimen traced.
Provenance
The Lost Collection of Simon English Esq.
H K Hepburn-Wright, collection dispersed by Spink, 15 April 1964 - £200.0.0
V J E Ryan, Part I, Glendining, 28-30 June 1950, lot 551

Estimate: £4000 - £6000