The private sector had a partial solution in creating tokens that were similar in size to pennies. Here is one interesting example.
On the West Coast, miners had the ears of the legislators and paper money was not to be found from San Francisco to Alaska.
Travelers headed East could trade their gold, silver, and copper for paper currency and often did at a better exchange rate than face value.
Because of the daily use of copper, silver, and gold coins minted in San Francisco, S mint marked coins are often harder to find in uncirculated condition than those produced in Philadelphia.