My friend F. went personally to a post office in Krugersdorp, South Africa, and obtained the postmark for this, and for other UNIKAT maximum cards (without duplicates) that she created at my request, for me.
Thank you, again! :)
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By the way, what do you understand if I say "This maximum card is UNIQUE?"
Well, it may mean different things, to different people.
It may mean that it has an unusual, original design - but how many copies have been manufactured from this design? Several?
It may mean that this specific configuration stamp+postmark+postcard was created by only one collector, but she may have obtained 100 "duplicates", "copies", all identical.
What I wanted to say is that THERE IS NO COPY of it - only one specimen of this maximum card.
So, why don't I invent a word in the English language, that is a noun (not an adjective): UNICATE.
It means that there's only 1 (one) in the whole world.
No DUPLICATE, no TRIPLICATE, etc.
This maximum card is a UNICATE.
There is already such a noun in German: UNIKAT.
From there, it was adopted in Romanian: UNICAT.
So, why not in English, too: UNICATE, to rhyme with DUPLICATE and TRIPLICATE.
:)