Major changes in composition and design resulted in 3 types of 1864 Indian cents.
The hard copper-nickel continued to be a major problem, causing rapid die wear. The public had accepted private tokens minted in softer bronze, and by 1864 the Mint received approval to mint Indian cents in a similar manner. By the end of May 1864 the copper-nickel cent was discontinued and the bronze cent, composed of .950 copper and .050 tin and zinc, weighing 3.11 grams, became the standard. Approximately 20% of 1864 Indian cents were minted in copper-nickel and 80% in bronze.
The obverse was then modified near the end of 1864, resulting in 2 different bronze issues. An "L" for Longacre was added to the obverse on the lower ribbon behind the neck. His "signature" remained until the end of the series in 1909. The 1864 with "L" type represents approximately 15% of the bronze Indians Heads minted in 1864, and are fairly scarce in gem condition. The "L" struck 1864s are also unique for their 1860 type pointed bust.