Numerous Talmudic discussions (Kiddushin 9-12, B"M 44 and more) refer to coins that were in use by Moses (in Moses times, i.e. in the desert, I presume), some that the Torah mentions, like Shekel, Gera, Sela and some that does not - Peruta, Isar, Dinar and more.
If I understand right, the only valuables (money, jewelry, precious metals) that were possessed by the Hebrews immediately after the Exile (ביזת מצריים) were those of Egypt. The Torah (to my knowledge) does not mention the currency of Egypt, and according to the current historical evidences, there were no monetary currency at all.
The Rabbis of my Kollel in Jerusalem could not recall anybody mentioning Moses melting the metals down and minting new coins of the Hebrews.
So, did Moses mint the coins the Talmud mentions about him, and if not, how did they learn the monetary values of the Torah, beside weighting the silver Shekel?