©Lin Yangchen

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After the war, more than four million stamps in Kuala Lumpur remained untouched by the Japanese. They were overprinted locally with BMA MALAYA under the supervision of Captain H. Holland (Cockburn 1998), who is thought to have experienced teething problems with inks (Pollard 2000a, Cockburn 2016b). The mixing of inks was an 'imprecise art' in those days (Fernbank 2013). Thus were born the mutated overprint shades of magenta and orange (Cameron 1950, Turner 1964, Lake 1965, Holley 2016) amidst the radioactive fallout of World War II.

The magenta overprint occurs in two forms which I refer to as smudgy and crisp. The smudgy form, which also exists in orange, is regarded as an unsuccessful trial that escaped from the printer, while the crisp form is regarded as a legitimate issue (Cockburn 2016b).

The smudgy magenta and orange trial overprints. Scans reproduced with the kind permission of Neil Macdonald. The orange overprints apparently took a holiday in Botswana before being rediscovered (Peter Cockburn comm. 2021)!

The crisp, issued form of the magenta overprint (centre) is flanked by a blood-red overprint on chalky paper (left) and a lighter scarlet on substitute paper with the key plate in a slightly lighter shade than the duty plate (right). This specimen of magenta was examined and verified by Norris (2016a).

The magenta overprint (upper row) in daylight (left) and 365 nm long-wave ultraviolet radiation (right), showing the 'volcanic lava' fluorescence characteristic of aniline-based inks (Lin 2017a). In the lower row is the red overprint under the same experimental treatment showing no signal. Rodgers (2017) subsequently corroborated the fluorescence and patchiness of ink on another copy of the magenta overprint.

Fluorescence spectrum (raw data) of the magenta overprint on excitation with a 325 nm helium-cadmium ultraviolet laser through a 40× fused silica-calcium fluoride microscope objective. The signal has a main peak coinciding with that of a highly fluorescent shade of the Selangor coconut definitive 10 cents magenta, but the fluorescence of the former is even stronger, perhaps because of higher pigment purity or concentration. The magenta overprint also has an additional peak absent from the Selangor stamp, indicating the presence of a constituent not found in the latter.

Yet another variation on red was the "metallic" overprint reported on some examples of the 50 cents. The ink is a strong red that appears thicker over the green paper than over the black ink of the stamp design. These tiny heterogeneities appear as a sheen to the naked eye, accentuated by the darkness of the green paper.

Energy-dispersive X-ray spectroscopy indicates that the red overprint is composed of red lead (Lin 2020d). Barium has relatively strong peaks in the metallic overprint; this may be a contributing factor to the brightness of the overprint ink. The green paper and black ink of the 50 cents make it a particularly dark stamp.

The X-ray spectrum from the magenta overprint seems to show paper coating and little else. This could mean an organic dye such as mauveine or alizarin, the latter of which can take on a pinkish shade depending on the mordant used. Both pigments fluoresce orange, as does the magenta overprint. Aluminium sulphate—whose elements appear to be present—could have been used to fix pigment to paper as was commonly done.

Backscattered electron images from a scanning electron microscope, showing the presence of heavy metal in a red overprint (left) and the absence of heavy metal in a magenta overprint (right).

Literature on the magenta overprint has so far described the shade, reported specific examples encountered by collectors and postulated teething problems with ink (Holley 2016). This study makes forays into chemistry for the first time. It reinforces the idea that postal authorities may have been using a different pigment altogether, one with which a true shade of red seemed very difficult if not impossible to obtain. Was lead oxide not available, and why? Could they have sourced the organic dye from the textile industry as a stopgap? Chemical analysis helps generate further historical and cultural questions.

A partially buried strip of 1-cent stamps on the back of a reused envelope.

I am grateful to Neil Macdonald, Wulf Hofbauer and Li Zhen for their valuable discussions and assistance.


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