Canada #529, 533-534 10c 1970 Christmas and 1971 Rutherford & Insulin Issues, Combination Usage on 68c Oversize Registered Cover to the US, Sent May 6, 1971

An oversize airmail cover to the USA, sent on May 9, 1971 and franked with inscription blocks of the 1971 Rutherford and Insulin issues, plus a pair of the 10c 1970 Christmas issue on HB ribbed paper. Together these paid the 50c registration fee plus 18c postage on an oversize item. A nice example of an unusual rate, as very few oversize covers like this would have been saved. There is a crease and tear at the top of the Insulin block, which was there before the block was affixed, most likely, and there is an edge tear at the top which stops just short of the Rutherford plate block. Despite these small issues this is still a nice cover.

Est $10.

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