Great Britain 1967 4d British wild flowers SG720c.
A superb unmounted original gum se-tenant block of four with reddish purple omitted, offered with normal for comparison.
The missing colour affects just the bottom right stamp from the block resulting in the loss of flowers and leaf shading on the Red Campion and shading on the Wood Anemone.
A very scarce QEII error. Pierron records only 30 mint blocks.