Some explanations on cancels and cancelled to order on stamps from
https://www.linns.com/news/postal-updates-page/stamp-collecting-basics/1998/may/postage-stamps-that-are-canceled-to-order.htmlWhen a stamp is used on a mailed item to pay for postage it usually receives a postmark to prevent anyone from using the stamp again.
Some stamps are canceled-to-order, and are known among collectors as "CTO." But why do stamp collectors find postmarked stamps that have full, unused gum on the back?
There are several reasons why CTOs exist.
For the governments of some countries, selling canceled, unused stamps at a discount directly to stamp dealers has provided additional income.
Such countries print mint, uncanceled stamps for use as postage, to be sold at the post office. They also have created canceled-to-order versions of the same stamps for sale to stamp dealers or stamp wholesalers.
Stamp dealers use the supply of canceled stamps to create packets to sell to collectors. The postal authority profits from the sale of the stamps without having to provide postal delivery services. The stamps can never be used for postage in the future because they are canceled with a postmark.
The postal authority prints sheets of stamps with postmarks placed to mark every stamp on the sheet. An example is shown in Figure 1. Bulgaria Scott 3591 is a 10-lev definitive stamp from 1991 depicting a cow.
The stamp was printed in sheets of 100. A circular cancellation mark is printed 25 times on the sheet.
Each mark covers four stamps, as shown in the enlarged illustration. This unused sheet has stamp gum on the back, just like any new stamp issue.
The presence of stamp gum on the back of a canceled stamp is the easiest way to identify a CTO.
A crisp sharp cancel perfectly marking the corner of one stamp is another clue that a stamp might be a CTO. This is particularly true for stamps that have cancels printed on them.
In other cases, the CTO may look more like a stamp that traveled through the mail.
The postmark on Czechoslovakia Scott 1740, a 1971 definitive stamp shown in Figure 2, is paler than the crisp bold marking on the Bulgarian stamp, and it bears a pair of wavy cancellation bars trailing the circular marking. The Czech postmark more closely resembles the kind of mark one might expect to find on a stamp that has journeyed through the mail.
A look at the back of the same stamp, however, shows that it has full gum and never fulfilled postal duty.
The Scott catalog listings for Bulgaria include a notice about canceled-to-order stamps of that country.
"Beginning about 1956, some issues were sold in sheets canceled to order. Values in second column when much less than unused are for 'CTO' copies. Postally used stamps are valued at slightly less than, or the same as, unused."
A similar notice appears among the Scott listings for stamps from Czechoslovakia and other entities that create and sell canceled-to-order stamps.
Many of the countries that have issued CTO stamps are former Eastern European communist bloc nations, including Albania, East Germany, Hungary, Romania and Russia, as well as Bulgaria and Czechoslovakia. Most of these countries began marketing CTOs during the 1950s and stopped after 1991.
During the 1960s, the stamp market was flooded with CTOs from the Trucial States of the Arabian peninsula. Many of the stamps produced by these entities — Ajman, Dubai, Fujeira, Manama, Ras al-Khaima and Sharjah — are not recognized in the Scott catalog because evidence suggests that actual postal use of these stamps was negligible.
Other countries that have issued CTOs include Costa Rica (during the 1910s), Spain (from 1854-82), Liberia (beginning in 1885), and several more.
In the April 29, 1996, edition of Linn's Stamp News, Michael Schreiber reported on mint United States stamps that were marked with a roller-cancel by a local postmaster for use as a receipt of a major stamp marketing firm's postage due bill payment.
The firm then sold the stamps, with full gum on the back, to customers requesting used copies of recent U.S. commemoratives.
The customer who wrote to Linn's provided the 1995 32¢ Winton Automobile stamp, Scott 3022, shown in Figure 3. She was concerned that the stamp might be a CTO.
In this case, the stamp actually fulfilled a postal function. As the article explained, the use of postage stamps as a receipt for a postage due bill payment is an approved postal service procedure. Though with full gum on the back the stamp resembles a CTO, it is, in fact, what is known as a favor cancel.
Whenever a collector or postal customer specifically requests a cancel or postmark, the result is known as a favor cancel.
Another example of a favor cancel is shown in Figure 4. The Paris Disneyland postmark from France applied to the 1997 Happy Birthday stamp (France Scott 2556) is not a standard machine-applied cancellation one normally finds on mail. Instead, it is carefully struck by hand on a postcard souvenir for the benefit of a collector.
From time to time, Denmark's postal service uses removable paper note stickers with diagrams that instruct clerks how to properly place a favor cancel on a mailed philatelic package (one going to or from a collector).
For some collectors, only cancels created by normal mail processing procedures are acceptable. Other collectors notice that CTOs and favor cancels are neatly applied and usually do not physically damage the stamps, which is a hazard of machine-applied cancels.
CTOs packaged in packets have been used for many years to introduce new collectors to the hobby. Though the CTO stamps may never have fulfilled a postal function, they are inexpensive collectible items that have been used to help promote the growth of the hobby.
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