8.Postage due stamps.
This 1971 airmail cover to Australia has the 25c airmail rate paid using four different 1971 commemorative issues plus the 1c Centennial definitive - a very unusual thing to find, since most of these covers would have been paid with a 15c stamp plus a 10c stamp, or a 25c stamp. It is unsual enough to find four 6c stamps, but to find all four from a different and CURRENT commemorative issue, is a real treat.
So what to look for in the postal history then? Well there are several things to look out for:
- Covers used to exotic destinations where the rates are paid with in-period definitives of commemoratives.
- Covers to common destinations, but where highly unsual, in-period stamps have been used to pay the rate. Generally speaking, the more different stamps used, the better the cover is. So for example a 15c airmail cover from 1959 that bears three different 5c commemoratives from 1959 is a much better cover than one that has a strip of three of the same commemorative. That cover, in turn is much more desirable than one that bears a single 15c definitive, which would have been the most common usage of the time.
- Any cover that has a proper usage of a se-tenant pair, block, booklet pane, souvenir sheet.
- Covers with unusual cancellations and cachets, such as hand-painted cachets.
Unfortunately many of the field stock sheets have been broken up before their significance was well understood, with the result that many of the scarcer paper types no longer exist in full sheets. This is still a relatively new field in Canadian philately and although many discoveries have been made over the years, there are still more discoveries to be made for sure.
Modern Paper Varieties
Up until 1983 most of the modern issues after about 1971 were printed on a chalk-surfaced paper manufactured by a company called Abitibi-Price. In 1983 Abitibi-Price went out of business and Canada Post was forced to seek out alternate paper suppliers. Quite a number of suppliers have been utilized since then including:
- Coated papers