n 1666, during the Russo-Polish War of 1654 - 1667, an experimental auksinas was minted at the Lithuanian Mint. It was a silver coin of very low quality: silver was only about 50% of its mass. It measured about 33 millimetres in diameter and weighted about 6.72 grams (0.237 oz). Officially, it was worth 30 groschen, while its real value was only about 12 groschen. It was equivalent to the so-called tymf (pl) coins minted at the Bydgoszcz Mint in 1663 - 1666. The only difference was in the coat of arms on the reverse: instead of the coat of arms of the Commonwealth, it showed only the Lithuanian vytis. The obverse had the royal monogram ICR (Ioannes Casimirus Rex for John II Casimir Vasa) and a patriotic slogan DAT PRETIVM SERVATA SALVS POTIOR Q(am) METALLO EST (rescue of the homeland is valued more than metal), while the averse (reverse) had MONET(a) NOV(a) ARG(entea) LITVANIA(e) (new silver Lithuanian coin).
This auksinas was never mass-produced and the only surviving specimen is kept by the Hermitage Museum in Saint Petersburg.