Adding to John's comment:
Back in the day, merchants had to pay sales tax to the state on the total amount of sales made by the merchant during each day’s sales. You can imagine that if the sales tax rate is 3% and a child buys a 10c piece of candy there is no way to collect the three-tenths of one cent. If you rounded down that meant that the merchant could not collect anything for the tax. If you rounded up the state was gaining 7 tenths of a cent on every 10 cent sale. You can see that if the merchant sold 100 pieces of candy he was losing 30 cents a day in tax revenues to the state, so the token was born. This allowed the merchant to take 11 cents for the first piece of candy and give change back in mills. The next time you wanted to buy a 10c candy you could present the merchant with the 10c and a token and complete the transaction. This allowed the merchant to collect the sales tax on each transaction.
A mill is a tenth of a cent. As you can imagine, people did not like having to carry a second set of coins, and to further complicate matters, different states issued different tax tokens. 1 and 5 mills are the most common denominations, but other denominations include: 1/5 cent, 1 1/2 mills, and "Tax on 10c or less."
Most coin dealers have no idea what to charge for these tokens, Many tax tokens are quite common, and can often be found in coin dealer "junk boxes" for as little as 10 cents. Others tokens are known to be much scarcer, however they too sometimes show up in ‘junk boxes’ from time to time.
In addition to tokens many towns printed sales tax "tickets" or scrip (sometimes spelled script) printed on paper or cardboard stock, usually on vibrant colors or security patterns. State sales tax token composition varied: copper, brass, paper, cardboard, fiber, aluminum, zinc, plastic and even wood was used.
Don…