Two Penny Blue Stamp issued in 6th of May 1840 is the worlds second official postage stamp. Everyone know about the Penny Black which the fist stamp but not many know about this second stamp. Two Penny Blue stamp is significantly rarer and more expensive than the Penny Black. Even though you could find a low quality stamp for every cheap in Ebay, a stamp in perfect condition would cost you upto 25,000 USD. Specially if you find mint blocks etc.