A semi translucent thinning of the substance of paper base. It is usually a device, pattern, or lettering produced by the pressure of wire on brass forms called “bits” attached to the roll of a paper making machine.
Watermarks can be detected by:
- Visual – turn the stamp face down on a piece of black paper or a black surface of some kind.
- Watermark fluid in black tray
- Ultra Violet light
A series of found or other shaped holes punched out between the rows of stamps in a sheet or coil strips of stamps to facilitate the separation of an individual stamp.
The three methods in use today:
- Line or guillotine: one straight row of punches perforates a line at a time.
- Comb : three sides of each stamp of a row are done at one stroke.
- Harrow: a whole block pane or sheet is perforated in one operation.
Perforations are measured by the number of holes (perfs) to 20 mm or 2 centimeters. Horizontal given (top side) first, then (right) vertical, then if necessary, the bottom.
Postmarks are those parts of the cancellation which indicate date, time and place of posting. This is the most common type of postmark in use today. Postmarks are known by other names: obliterator, killer, or by the type of cancel (heavy lines or bars), cork cancel (early devices carved out of cork or wood), slogan cancel (containing some slogan or trademark), gridiron cancel (generally oval shaped) or other designations to indicate the method of transport such as ship cancel, railroad cancel, mailboat (paquebot) cancel or airmail cancel.
Do you love trains, airplanes, baseball, birds, space, fish, olympics, or anything else? Topical collecting allows anyone collect on stamps the things that interest them without rules to follow and spaces to fill in an album. Each person collects their interests and is free to organize their stamps in the ways they like best. For those who want the help of a album to fill, publishers offer topical pages for popular topics. Or you can make your own pages the way you want them.