Absinthe "the holy trinity." Many other herbs may be used as well, such as petite wormwood ("Artemisia pontica" or Roman wormwood), hyssop, melissa, star anise, angelica, peppermint, coriander, and veronica. Adding to absinthe's negative reputation in the late 19th and early 20th centuries, unscrupulous makers of the drink omitted the traditional colouring phase of production in favour of adding toxic copper salts to artificially induce a green tint. This practice may be responsible for some of the alleged toxicity historically associated with this beverage. Many modern day producers resort to similar (but non-deadly) shortcuts, including the use of artificial food colouring
Mint-made errors from intentional recycling of the die. An overmintmark occurs when a second mintmark is punched over an earlier mintmark following the transfer of a die from one mint to another. A well-known example is the 1900 Morgan silver dollar, when reverse dies with "CC" below the eagle were sent from the Carson City Mint to the New Orleans Mint, where they were given an "O". A similar case occurred in 1938, when a reverse die for the buffalo nickel was made for the San Francisco Mint, because that year only, the Denver Mint made these coins with a "D" punched