Mary (1542-1567), Fourth period, Ryal, 1566, mm. thistle on rev. only, 29.28g/8h (SCBI 35, 1123-4; SCBI 58, 1172ff; B 6, fig. 905; S 5425 and p.76). With crowned thistle countermark for the revaluation of 1578 on reverse, about fine £300-400