Same Stamp But Different Stamp

On March 14, 1953 the DDR issued a set of 10 stamps commemorating the 70th anniversary of the death of Karl Marx. The stamps were printed by photogravure in sheets of 50. There are two watermark types of these stamps.

One of these stamps, the 24 pf (Michel #349) exists in two varieties, with the "DEMOKRATISCHE REPUBLIK" inscription being 22.2mm in length in the first type, and 21.5mm in length in the second type. Examination under 10x shows that these are from two differently prepared plates. The "cells" of the type II stamps are much more precise.

Here is the one shilling value from New Zealand's 1947-52 KGVI definitive series. Two different plate varieties are listed by Stanley Gibbons. Left stamp is plate 1, with lighter shading lines/vignetting behind the king's portrait. The right stamp, plate 2, shows more and heavier shading lines in the vignetting.

The Republic of China Double Carp II stamps (1969 to 1978) are known for variations in perforation and paper types.
Left: fibrous paper, line perf 12 – 13 variable (1969)
Middle: low fiber white paper, comb perf 13½ x 12½ (1975)
Right: fibrous paper, comb perf 13½ x 12½ (1976)

During the last 4+ years of the period when Germany allowed private intracity mail courier service (Sept. 25, 1896 - March 31, 1900), Wilhelm Boettcher & Co. operated Privat-Stadtpost Courier in Munich. All five of the stamps issued by this company depict the "Munich child" image as shown here. Three of the stamps are 1 1/2 pf values printed in dark blue, and perforated 11 1/2.

Here are the first and last stamps of Privat-Stadtpost Courier. The first (Mi #1), issued in September 1896, shows a small halo on the Munich child, and the lettering is well formed, among other differences.

The second stamp (Mi #5), issued in 1898, shows a larger halo on the Munich child, and the lettering is rather crudely formed, most notably the "S" of "POST".

The 50c value of Singapore's "Tropical Marine Fish" definitive series depicts a yellow-faced angelfish (Pomacanthus xanthometopon). On February 3, 2004 the stamp (SG #1132, type I) was released with a misspelling of the species name. On March 18, 2005 a second version of the stamp (SG #1132a, type II) was issued with corrected species name.

This Sweden 2017 Retro Stringhylla stamp has two formats -
Left: comb 13 x 13, from sheet with ordinary gum
Right: die-cut 13½ x 13½ with security marks, from self-adhesive coil

These Serbia Girth with a buckle definitive stamps bear the imprint of 2010, 2012, 2013, 2015, 2017, 2018, with slightly variable stamp size.

The NVI (no value indicated), 1st and 2nd class, self-adhesive Machin definitive stamps of the U.K. may look identical, but there are "built in" differences, depending on the year, printer, and format. The five different 1st class rate stamps shown here are all from 2014. All of their internal "c"-shaped die cuts have a small uncut space in the middle of the "c", but it varies minutely on the first and fourth stamps.

The iridescent "Royal Mail" overprinting has a different code on each of the stamps. Although each stamp has the same "M14L" code in front of the crown, each stamp has a different code behind the crown. They are listed below, indicating the printer and format/source. This information was found at "The Machin Nut" website

The scanner does not pick up details/reflection from the iridescent printing, so second pic showing the "MCIL" variety was taken with cel phone.

MAIL De la Rue
MBIL Walsall Business Sheet
MCIL Walsall Mixed Booklet
MSIL Walsall Booklet of Six
MTIL Walsall Booklet of Twelve

The Saudi Arabia definitives of the 1960's - 1970's pose a number of challenges for collectors. Aside from watermarks, which can cover an area of four stamps, the cartouches (oval calligraphic arabic name) of Kings Saud and Faisal can appear to resemble each other.
The two examples below, coincidentally paired with labels supporting the Al-Fateh movement, are from the reign of King Faisal (left) and King Saud (right):


King Faisal cartouche

King Saud cartouche



Incidentally, King Faisal's reign was from November 1964 to March 1975, however stamps with the cartouche of King Saud were still being produced and used during this period, and stamps with both cartouches can appear together on mail from this era.
Faisal

Saud

Lebanon has had to introduce various measures to prevent illicit use of stolen stamp stocks. One was the introduction of the "fleuron" (little flower) overprint applied to commemorative issues during the late 1990's.
One example is the 1995 Martyr's Day Monument issue.
Original

1999 re-issue

1999 (14 Aug) further re-issue

Note the orientation of the fleuron in the overprinted versions.
There is also a significant variation in catalogue price of each version, making it essential to take extra care when acquiring such stamps on internet sales platforms, particularly when the stamps have heavy cancels.
Of course, not all sellers understand these variations....

Finland's engraved "Lion" definitive series was in use from 1954 until 1975 when the "Coat of Arms" series began. From 1963-75 the Lion stamps were issued in decimalized denominations. These sheet and booklet stamps were printed on different papers, and some are on phosphor-coated stock.

From 1967 onwards, the stamps were printed on differently engraved plates (type II). The 0.30 mk blue gray stamp shown here illustrates the printing differences between the earlier type I printings and the type II stamps.

The DDR initiated its "Development in the DDR" series in April 1973 with the first issues in a large format (29mm x 24mm size). All of the 15 values in this set were issued in 50 stamp (5 x 10) sheets, and all were intaglio printed.

In July of 1973, the DDR began issuing smaller-sized versions (21.5 x 17.5mm) of some of the "Development" stamps for use as coil stamps. These first, small stamps are rotogravure (high speed, rotary press gravure) printings. From 1973 to 1975, 6 values were issued: 5, 10, 20, 25, and 50 pf, and a 1 mark stamp. Only the 10 and 20 pf values were printed in both coil and sheet (10 x 10) formats. All values were printed in coil format.

Beginning in 1980, the DDR began replacing the large format "Development " series sheet stamps with small format intaglio-printed "Development" series sheet stamps. From 1980 to 1985, 15 different values of these stamps were issued, all of them in sheets of 100 (10 x 10).

Here are the two printing types of the small format stamps shown for comparison.

Finland Brown Bear Cub definitive issue
2004 print (left): Latin name Ursus arctos smaller, luokka klass typeface thinner
2009 reprint (right): Latin name Ursus arctos larger, luokka klass typeface thicker

Switzerland 1999 Postal Service Pingu
March print: packages with strings (top row)
December print: packages with no strings (bottom row)

Ireland
Birds Definitive - Common Blackbird
Top left: perf comb 14 x 15 (1998)
Top center: perf comb 14 x 15, top or bottom imperf (1998)
Top right: perf comb 14 (1998)
Lower left: perf 9 x 10 die cut, phosphor frame (1998)
Lower center: perf 9 die cut, phosphor frame (2001)
Lower right: perf comb 11 x 13, top or bottom imperf (2001)