1913-34 Seahorses: 1913 Waterlow 2s.6d. imperforate plate proof in black, on thin wove paper, fine and rare. Photo. (Image1)

1913-34 Seahorses: 1913 Waterlow 2s.6d. very deep sepia brown (Vandyke brown) overprinted “SPECIMEN” type 26, fine with gum. Brandon certificate (2023). S.G. N63(1)s. Photo. (Image1)

1913-34 Seahorses: 1913 Waterlow 2s.6d. (2), 5s. and 10s. mint, varied condition. Photo. (Image1)

1913-34 Seahorses: 1913 Waterlow 2s.6d. very deep (‘van Dyke’) sepia-brown, fine unmounted mint. Brandon certificate (2015). S.G. N63(1), cat. £2,750. Photo. (Image1)

1913-34 Seahorses: 1913 Waterlow 2s.6d. sepia, fine unmounted mint example from the upper left corner of the sheet. S.G. . Photo. (Image1)

1913-34 Seahorses: 1913 Waterlow 2s.6d. dull grey-brown unmounted mint marginal example, fine. S.G. N63 var. Hendon certificate (2022). Photo. (Image1)

1913-34 Seahorses: 1913 Waterlow 5s. rough plate proof in carmine on buff unwatermarked paper, block of four, fine. Photo. (Image1)

1913-34 Seahorses: 1913 Waterlow 5s. pale rose-carmine very fine and fresh unmounted mint pair from the top of the sheet. S.G. 401. Photo. (Image1)

1913-34 Seahorses: 1913 Waterlow 5s. deep carmine-red, a very fine unmounted mint pair from the top of the sheet. Hendon certificate (2017). Photo. (Image1)

1913-34 Seahorses: 1913 Waterlow 10s. indigo-blue very fine and fresh unmounted mint block of four. Brandon certificate (2018). S.G. 402, cat. £8,000 as singles. Photo. (Image1)

1913-34 Seahorses: 1913 Waterlow 10s. indigo-blue, unmounted mint marginal block of four, fine. S.G. 402, cat. £7,200+. Brandon certificate (2000). Photo. (Image1)

1913-34 Seahorses: 1913 Waterlow 10s. indigo-blue, intense shade, good centring and unmounted mint. Very scarce. Brandon certificate (2005). S.G. 402, cat. £1,500. Photo. (Image1)

1913-34 Seahorses: 1913 Waterlow 10s. indigo-blue, intense shade, good centring and unmounted mint. Very scarce. Brandon certificate (2005). S.G. £1,500. Photo. (Image1)

1913-34 Seahorses: 1913 Waterlow 10s. indigo-blue, vertical corner marginal pair with light individual c.d.s’s. Scarce. S.G. 402 . Photo. (Image1)

1913-34 Seahorses: 1913 Waterlow £1 deep green overprinted “SPECIMEN” type 26, fine with gum, adhesion on reverse. S.G. 403s, cat. £3,000. Photo. (Image1)

1913-34 Seahorses: 1913 Waterlow £1 green, unmounted mint, fine. S.G. 403, cat. £3,800. Photo. (Image1)

1913-34 Seahorses: 1913 Waterlow £1 green, bright mint shade, fine. S.G. 403. Photo. (Image1)

1913-34 Seahorses: 1913 Waterlow £1 green, fine used. S.G. Spec. N72(1), cat. £1,400. Photo. (Image1)

1913-34 Seahorses: 1913 Waterlow £1 green, fine used. S.G. 403, cat. £1,400. Photo. (Image1)

1913-34 Seahorses: 1913 Waterlow £1 green, fine used. S.G. 403, cat. £1,400. Photo. (Image1)

1913-34 Seahorses: 1913 Waterlow £1 dull blue-green, mint, gum wrinkle, otherwise fine. S.G. 404, cat. £3,800. Photo. (Image1)