Odd flaw on 97p Christmas Wallace & Gromit

I've been sent this picture of an odd flaw - which appears to be properly screened - at the foot of a 97p Christmas stamp:

The flaw is not composed of any single colour from the CMYK group, and seems to be partly a mix of yellow and black, and partly of cyan and black.  It could be a 'foreign body' in the print - it isn't a 'foreign body' on the stamp itself.

Has anybody seen anything similar on this set or others, or any explanation of this flaw.  Let us know by using the Comment faclity!

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Litho ring flaw on London 2010 Festival of Stamps Souvenir Sheet

Two different ring flaws have been found on the 1p stamp in this sheet. 

From the position they could have the same origin - or they may be from two different parts of the press sheet.  We have seen several of each in our stocks - also on FDCs, now available on our e-commerce site.

Send us your finds!

Constant flaw on Darwin's Machin PSB pane

An eagle-eyed collector in Singapore has spotted something that two dealers handling his stamps failed to spot, and that is a constant flaw on one stamp on this pane.

It might have been a fleck of paper, except that it appeared on all the panes in my stockbook. And it might have been on every Machin pane - except that it isn't any of the panes I have with the dark 5p stamp, and it isn't on any of the panes in the books I have, or the FDCs. But it is constant on at least 20 panes!

More next week when I will have had a chance to scan it.