Canada #562, 584 8c Buffalo Chase & 15c Multicoloured 1972 Earth Sciences Issue, Combination Usage of Photogrammetry on Airmail Cover to Germany 2 Days After Issue

A mysterious airmail cover to Germany, which was sent on August 4, 1972, just 2 days after the Earth Sciences Issue was released, and was curiously franked with 23c postage, which does not correspond to any rate in effect at the time. The best I could determine is that the letter was just over an ounce and because it was less than an ounce and a half, the sender added an additional 50% to the 15c rate, not understanding that the correct rate was 30c. It would appear that nobody else caught this, as there are no postage due or shortpaid markings on it. This is a very nice early usage of this issue - the earliest I have seen.

Est $25, based on the note in Unitrade, and adding extra for the double rate.

To gain a better understanding of what I consider in valuing covers, you might find it useful to read the blog post here.