differents types: Blue, white surface, white gum (shades)
'BF' for 'OF'
'UF' for 'OF'
'O' and 'F' tied together
Parts of 'G' missing
Vertical mark below and to the right of the second 'A' in AFRIKA Row 1/8
Line from right side of crown through to the Transvaal shield. Row 6/1 of later printings