The line of shading in the left acanthus is often well-defined in the Type III stamp.

The line of shading in the left acanthus is never fully defined in the Type IV stamp.

Poorly inked Type IIIs will not show the well-defined line of shading in the acanthus and exceptionally sharp Type IV stamps may show parts of the line, but never as much as in the Type III example given above.

All the Type III examples are from the same scanned stamp from plate number 146, and all the Type IV examples are from the same scanned stamp from plate number 762.