As already stated, Stanley Gibbons catalog does not mention this one. I presume it is SG190 (Scott#101) lilac twopence halfpenny? Normally this type of variety has to be "constant" which means it appears in the same place on other sheets of stamps as well.
Without seeing it as a scan it cannot be assessed or guessed at.
Your K could be the result of damage in transit thru the post or a postmark appearing to give it a different shape or a transient speck of dust on the printing plate when being printed... or some other cause.
Being a Victorian stamp it could be assumed that this K would have been seen by others over the past century or so. I think constant flaw could then be dismissed.
Post a scan as it would be of great interest to see and speculate. A normal stamp would be worth around UK £1 in average condition.
Posted 05/03/2015 10:47 pm
