Hello,
Not sure about what you call patterns. For me they are essais, trial strikes, hence necessarily rare.
In that case, that may be just a silver version on a gold coin, using the same dies. This was more common.
Krause classifies them as patterns but you notice that the seller says "silberabschlag" or silver strike, which may be different and mean 10 versus 2000 minted.
I came through a similar case for Salzburg commemos
https://en.numista.com/catalogue/pieces84972.html
For the specialized catalogue by H Zottl, it is silver for 5 kreuzer, 1 ducat dies. There is a 10 kreuzer with 2 ducats dies which is as pattern in the WC with pn number. Not that common but not very rare either. So there is some confusion.
Quand l'Histoire et la Géographie se croisent sur nos pièces de monnaie ...
Referee for Austria-Habsburg, Austrian Netherlands, Austrian States, Bohemia, Silesia.
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