Complex sentence: Neither the silver dollar nor the eagle had been struck since 1804, but they were still considered current coins, but putting the date of striking on the pieces would make them appear them appear to be in violation of Jefferson's prohibition which remained in force.
Split into simpler sentences: Neither the silver dollar nor the eagle had been struck since 1804, but they were still considered current coins. Putting the date of striking on the pieces would make them appear them appear to be in violation of Jefferson's prohibition which remained in force.