By Charles Snee
Stamps sometimes come with attachments that can often reveal clues about their origins and, in some cases, enhance their value. Take a close look at the two United States 2¢ Battle of Fallen Timbers stamps pictured in Figure 1. Do you notice anything different?
On recent United States stamps, you might see printed on the selvage pricing information, a copyright diagram, a pane position diagram, a tracking and inventory bar code, or supplementary text about the stamp.The stamp on the left has no attached margin paper, while the stamp on the right does. In this case, the margin paper is attached to the left side and bears the five-digit number of a line-engraved steel plate used to print the stamp. Such attached margin paper is called selvage and is an integral part of a sheet or pane of stamps. Selvage may be unprinted or may contain printer's markings or other information.
Many collectors of U.S. stamps are familiar with the terms plate block or "plate number block." Numbers identifying the printing plate used (most issues printed through the first half of the 20th century) or printing cylinder used (many modern issues of the last 20 years) typically appear somewhere on a printed sheet of U.S. stamps. The numbers were usually trimmed away during processing of early U.S. coil and booklet stamps.
A block is a unit of unsevered stamps that includes at least two stamps both horizontally and vertically. Most commonly, a block refers to a block of four, although blocks often contain more stamps and may be irregularly configured.
A plate block is a block of stamps from the corner or a side of a pane. It includes all surrounding selvage bearing the plate number(s) used to print the larger sheet from which the pane originated. For many U.S. stamps, a plate block has four stamps.
However, a plate block of some U.S. stamps printed in the 1970s might consist of six, eight or 10 or more stamps. This is because multiple plate numbers are strung along the selvage, requiring large plate blocks to show all the numbers.
Figure 2, bottom, shows a plate block of the 5¢ Olympic Games stamp of 1932 (Scott 719). Note that the plate number is printed on selvage attached to a corner stamp. For many earlier issues, though, plate numbers were printed near the center of the selvage on a pane.
Let's assume that you are new to plate-block collecting. How would you know that a plate block of 5¢ Olympic Games stamps consists of four stamps and not six or eight? The answer can be found in the ScottSpecialized Catalogue of United States Stamps and Covers. Near the end of the listing for Scott 719 is the description for a plate block: "P# block of 4."
Armed with this new-found knowledge, you can easily see that the multiple shown at top in Figure 2 is not a plate block. Even though the selvage bearing the plate number is attached, the multiple is properly called a pair.
When it comes to value, having the plate block sometimes contributes minimal or no value beyond a normal block. Numerous four-stamp plate blocks from the 1950s are listed in the Scott U.S. specialized catalog with values of 40¢, while a single stamp catalogs at 20¢. Warning: This does not mean you can increase the value of the stamps by breaking up your plate block.
The 20¢ value is the minimum value determined by the Scott Publishing Co. for single stamps, used or unused. Such stamps don't have a noticeable premium as plate blocks. But for many older stamps, a plate block commands a premium over the value of single stamps or a block.
The U.S. 5¢ Olympic Games stamp has a retail value of about $2.20 as an unused single. But a plate block is valued at $20 ($25 for never-hinged). Therefore, an unused plate block has a value nearly 2½ times greater than four single unused stamps.
In some cases, selvage condition also can affect value. The plate block of six pictured in Figure 3, top, has top margin paper that has been trimmed down from its original width, perhaps to make it fit easily on an album page.
A choice of convenience, yes, but a poor one, because the plate block would be worth more if it still had full, intact selvage, as does the plate block of six shown at bottom in Figure 3.
Of course selvage can often reveal interesting details about a given issue. For example, text in the surrounding selvage on the 2¢ White Plains souvenir sheet (Scott 630) pictured in Figure 4 states that the stamp was issued in conjunction with the International Philatelic Exhibition, held Oct. 16-23, 1926, in New York City.
The White Plains stamp (Scott 629) also was issued in standard panes of 100 that have plate numbers but no text about the exhibition in the selvage. Single stamps without selvage from both formats are identical and were issued the same day, Oct. 18, 1926, so the selvage plays an integral part in telling the two formats apart.
The selvage of many recent U.S. stamp panes bears colorful artwork in addition to text about the stamp(s). In some cases, text appears on both the front and back of the selvage and the stamps. Examples include the 32¢ Comic Strip Classics stamps of 1995 and the Stars and Stripes stamps of 2000.
Selvage also is important for collectors of booklet stamps. Up until about 12 years ago, stamps in booklets had moisture-activated gum (required licking), were perforated, and were sandwiched between cardboard covers.
A strip of attached margin paper often was used to affix the pane or panes to the inside of the cover. While this selvage is of little use to a mailer, a collector of booklet stamps demands that it remain attached to the pane.
Shown in Figure 5 is a booklet pane of three 6¢ Transport airmail stamps. The margin paper at top means that the pane is complete and is listed as Scott C25a in the Scott U.S. specialized catalog.
If the margin paper were missing, the pane would be incomplete — it could only be viewed as three attached single stamps. While these distinctions may seem subtle at first, they become critical to the collector as he pursues items to fill the holes in his album.
After all, a collector unfamiliar with the plate block for U.S. Scott 719 or the booklet pane for U.S. Scott C25a may accidentally buy a wrong or incomplete item.
For some recent U.S. stamps, selvage markings can explain where a pane originated on the larger sheet before it was processed. A pane position diagram is shown in the selvage of the 32¢ Civil War stamp pictured at top in Figure 6. The Civil War stamps were issued in 1995 in panes of 20.
The darkened square in the grid means that the stamp was part of the bottom-right pane of the original press sheet of six panes. Printed just below the grid is the plate number. The letter "S" prefix means that Stamp Venturers of Virginia printed the stamps.
The selvage of the 33¢ American Samoa stamp, Figure 6, bottom, bears a bar code that the U.S. Postal Service uses for tracking and inventory purposes.
If you are uncertain about whether selvage should be left or removed, you might want to consult the Scott U.S. specialized catalog to learn if the margin paper has any importance. Remember, being well informed can add immeasurably to your enjoyment and understanding of stamp collecting or any other hobby.