I had this for sale a while ago and removed it until I could get clarification on the value and legitimacy of the category.
It is Germany 510 and a single was listed on a stamp sales site as a sub category of 510_1. Is there someone that can verify the sub category as a color difference and the catalog value at apx. $7.00 per stamp in MNH condition?
Sorry for the shading on the right side. Guess my fat finger got in the way.