Date: 26 Elul
From: Rabbi Moshe Sofer
To: Rabbi Yoshua Katz
The Chasam Sofer calculates that twenty Zwanziger coins contain the required five selaim of pure silver for pidyon haben under the Konventionsmünze standard, recommending one or two extra coins as a stringency. He further rules that the Torah-law kesubah of 200 dinar equals 200 Zwanziger, that new imperial Bankozettel designated as 'good money' may be used to pay the statutory kesubah amount at face value, while the tosefes kesubah is subject to the Skala revaluation adjustment.
Source: Shu"t Chasam Sofer YD §289