The article presents two undescribed varieties of Prague grossi struck under John of Luxembourg. First, which can be identified as variety Castelin II. 9 and whose existence is confirmed by two pieces, is characterized by a double diagonal beam of N letter in the name of the king.
In the second variety, which can be determined as Castelin VI. 36, are all horizontal beams of A letters and diagonal beams of N letters are missing in the obverse marginal legends. Coins were also subjected to non-destructive analysis.