424  (Early Series)   Posy ring.
Does this shape appear in other series?   Yes, although the only recorded Early Series example is slightly larger than the Later Series version which is Later Series 163.
A similar posy ring also appeared as  'A' Series / Kerryl A111 .

There was also a half-ring version, Early Series 425

Diameter; 17.5 cm

Early Series 424 (left) with Later Series 163 (centre) and an un-numbered half-ring
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