The Mexican definitives have got dealt with in catalogues by now on the basis of the most popular definitive series - the Export series of 1975 - i.e. split up in a series of subsets according to the type of paper the stamps have been printed on. This is a very logical division as most definitives have been printed on quite a variety of papers. However, not all series should, in my humble opinion, be divided according to types of paper only. The more, that the different type of watermarks can be pretty hard to tell apart for collectors whose main source of material is the 'kiloware' kind of used, often heavily cancelled stamps. |
In order to understand the 1950 Architecture series, one must go a bit back into time. The time when the precursor of the main stamp printer in the post-war period. The Oficina Impresora de Hacienda [State Prinitng Works] have been printing Mexican definitives since 1915, mainly in recess/intaglio (the printing process proper for banknotes) but as it seems also in a probably hybrid process called 'screenless photogravure'. It's in the latter process that most definitives in the 1930-ies got printed. The perforations used by the Oficina Impresora de Hacienda had been standardized in 1934 so 2 different sizes were in use. The comlete sheet block got perforated in 2 blow (harrow):
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By 1936 the newly established [?] National Security Printing Works in Mexico DF, Talleres de Imprésion de Estampillas y Valores [TIEV] had introduced a smaller size, quite accordingly to the perforation gauges other printing works that were using GOEBEL-rotary photogravure presses: Comb 14 14/17 teeth horizontal/vertical. The Talleres de Imprésion de Estampillas y Valores have been printing Mexican stamps since 1936 in two major printing processes:
The first post-war large definitive series Architecture and Archeology was partly printed on the GOEBEL-press of the T.I.E.V. that could handle 2colours. Later on , in 1953 both a second press of GOEBEL (and a WIFAG was introduced to start printing stamps in recess. And later two more GOEBEL-presses to print more than 2 colours [i.e. 4 colours]. However, when we look at the perforation type used for the larger sized Airmail stamps of the Architecture series, it closely resembles the size and gauge the Oficina Impresora de Hacienda had been using in the 1930-ies: C 10 3/4:10 21/13 teeth horizontal/vertical and 40x25mm.. |
Not only the size plus gauge but also the printing process looks very much like the screenless photogravure so succesfully devised by the Leiden based Nederlandsche Rotogravure Maatschappij in a close cooperation with the GOEBEL-printing presses factory in Darmstadt, Germany; and also a printing process we meet in stamps - printed on GOEBEL rotaries ! - for the Vatican City [1929, Instituto Poligrafico dello Stato], South Africa [130-1948, State Printing Works in Pretoria] and last but not least Mexican definitives [1936-1937?, TIEV]. We may get even the impression that the stamps weren't printed on a GOEBEL-press at all, but on an earlier rotary-press that had been used by the Oficina Impresora de Hacienda! |
And indeed - as was pointed out to us in 2014 ! - the Oficina Impresora de Hacienda, later the TIEV had several - 10 copies - of a Waite and Saville -press! |
In judging the watermarks one should realise that a 'MEX-MEX' watermark that can be read horizontally might have 2 directions of paper: vertical or horizontal.
Luckily this wasn't always the case. Mostly, you will find that the definitives in traditional photogravure, the majority in this series, will have the combination [in case of a watermark] of a vertically read watermark line + horizontal paper fibres [horizontal 'cylinder']. Both the "MEX-MEX" and the "MEX" watermarks are orthogonal watermarks - i.e reading the watermark line and the direction of paper are perpendicular! The exception to this rule are several early 1950-ies printings that have the line "Gobierno Mexicano" run diagonally. |
Part of the Architecture series has been printed in more than one printing process and should therefore better be taken apart:
The Airmail stamps can easily be recognised by the perforation gauge: Comb 10 3/4:10 21/13 teeth horizontal/vertical. But what is more interesting is that all these show a vertical direction of paper (curling into a vertical cylinder!) in combination with a diagonally read watermark line (Paper type V- Gobierno Mexicano) or a horizontally read line (Paper type VI, horizontal "MEX-MEX"). No later Airmail stamp has a horizontally read watermark anymore! |
Paper type VI, vertically read line, can be the same watermark if the direction of paper is horizontal (curling into a horizontal cylinder). As the rotary press uses a continuous reel of paper, the stamps with a horizontal line will come out of the press - if you stand in front of the press and see the reel coming onto you - upright or upside down, the stamps with a vertical line will be turned 90 degrees and will meet you sideways. There is no way the same plate/cylinder can be used for both of these printing! The width of the printing cylinders must also have been different [assuming a 10x10 counter sheet]: either 10x40 = 40cm wide or 10x25 = 25 cm. The early GOEBEL-rotaries however were rather narrow plus/minus 32cm; later models could be slightly over 50cm. This once more points to another printing press which turned out to be a Wait&Saville (ex Oficina!). |
For the smal sized surface mail Peso stamps the perforation gauge Comb 14 1/17 first goes together with the vertical direction of paper (Paper V "Gobierno Mexicano", Paper VI horizontal "MEX-MEX") and was printed on a Waite&Saville; but then the 1 Peso with Comb 11 11/14 has a horizontal direction of paper (vertically read line) and was printed on the WIFAG. Subsequent small sized Peso definitives of this series that are also all printed in (screened) photogravure on a Goebel. |
All other stamps in this series that have been printed in photogravure from the start, were printed on the GOEBEL-rotary for sure and have a perforation gauge of 14 14/17 or 28/17; the latter being a variation of the first picking of the necessary abundant perforation pins! Stamps in screened photogravure with perforation 11 22/15 or 11 1/2:11 23/15 came from the WIFAG! |