1883-4 1½D LILAC AND GREEN COLOUR TRIAL. A very fine unused block of four of the 1½d value (SG188) printed in purple on pale grey UNWATERMARKED gummed paper, lower pair unmounted. A very rare multiple and apparently only 13 such blocks are known of which 8 are in the BPMA. Cat. £2,200. (Ref 103650).