gum breakers/ridges on US Kansas-Nebraska overprinted stamps
Jun 4, 2015 16:57:43 GMT -5
kacyds, Gordon Lee, and 4 more like this
Post by khj on Jun 4, 2015 16:57:43 GMT -5
Kansas-Nebraska overprints are one of the most heavily forged US stamps. Below is an example of a genuine US Scott #663.
One of the first quick tests to weed out forgeries on mint Kansas-Nebraska overprinted stamps is to check for gum breakers. Genuine overprints are always on the rotary press printed series of 1926. Therefore any overprint on a flat plate press printed stamp issue of 1922 is a forgery. While these 2 series can be distinguished by different perforations (1922 = perf 11, 1926 = perf 11x10.5), checking the gum breakers is easy if you don't have a perforation gauge handy. Gum breakers are NOT the same as gum ridges. This will be explained below.
In the picture below, you can barely make out a horizontal gum breaker at the 0mm level, as well as many vertical gum ridges. Sorry about the picture angle, but it was the only way I could get both the gum breakers and gum ridges to show up with the camera/lighting that I had. At least I used my high-tech philatelic grade Pixar Studios Cars ruler! These gum breakers were made by making a roller impression (indent) from the face side of the stamp. The purpose was to make a "break" in the gum to reducing curling of the mint panes after the press sheet was cut.
In the series of 1926, the gum breakers were made 22mm apart. So sometimes you can see a 2nd gum breaker on the series of 1926 (in the picture above, the next gum breaker is off the bottom edge of the stamp; the stamp originally below it most likely had 2 gum breakers). But in general, gum breakers on US stamps may be spaced from 5.5mm to 22mm apart, depending on the stamp issue. Also, they are NOT always perfectly horizontal, and it is not unusual to see them off-alignment by 5-10%. However, they will ALWAYS be parallel.
In the above picture, you will also see narrowly spaced vertical ridges. These gum ridges are also an artifact of rotary press printed stamps, but aren't always obvious. The gum ridges are actually created by the gumming roller. The gum breakers were made AFTER the gum was applied, and will ALWAYS be perpendicular to the gum ridges.
One of the first quick tests to weed out forgeries on mint Kansas-Nebraska overprinted stamps is to check for gum breakers. Genuine overprints are always on the rotary press printed series of 1926. Therefore any overprint on a flat plate press printed stamp issue of 1922 is a forgery. While these 2 series can be distinguished by different perforations (1922 = perf 11, 1926 = perf 11x10.5), checking the gum breakers is easy if you don't have a perforation gauge handy. Gum breakers are NOT the same as gum ridges. This will be explained below.
In the picture below, you can barely make out a horizontal gum breaker at the 0mm level, as well as many vertical gum ridges. Sorry about the picture angle, but it was the only way I could get both the gum breakers and gum ridges to show up with the camera/lighting that I had. At least I used my high-tech philatelic grade Pixar Studios Cars ruler! These gum breakers were made by making a roller impression (indent) from the face side of the stamp. The purpose was to make a "break" in the gum to reducing curling of the mint panes after the press sheet was cut.
In the series of 1926, the gum breakers were made 22mm apart. So sometimes you can see a 2nd gum breaker on the series of 1926 (in the picture above, the next gum breaker is off the bottom edge of the stamp; the stamp originally below it most likely had 2 gum breakers). But in general, gum breakers on US stamps may be spaced from 5.5mm to 22mm apart, depending on the stamp issue. Also, they are NOT always perfectly horizontal, and it is not unusual to see them off-alignment by 5-10%. However, they will ALWAYS be parallel.
In the above picture, you will also see narrowly spaced vertical ridges. These gum ridges are also an artifact of rotary press printed stamps, but aren't always obvious. The gum ridges are actually created by the gumming roller. The gum breakers were made AFTER the gum was applied, and will ALWAYS be perpendicular to the gum ridges.