Watch List notes:

Mary, billon plack, first period 1542 – 1558, eleven-twelves alloy, type d (d. 1557), crowned shield dividing MR, MARIA DEI G [SCOT]OR REGINA 1557, rev. ornate cross with plain cross in centre and crown in angles, [SER]VIO ET VSV TEROR 1557, wt. 1.83gms (S.5437), irregular flan, otherwise good, very fine
SCBI vol. 58, no. 971 cf
Richardson cf no. 179

Estimate: 150 - 200 GBP