John S. Ormsby of Pittsburgh, PA came to California with his brother, Major William M. Ormsby during the California Gold Rush. Records show that they left St. Joseph, Missouri by wagon train on April 14, 1849. When Dr. John Ormsby and his three brothers and J.K. Trumbo arrived in Sacramento, it was a city with a population of 5,000. Before the discovery of gold, there were about thirty white residents. The Ormsbys founded the first private mint in Sacramento and an assay office. They minted coins in 1849 and 1850 from native gold, which were readily accepted as legal tender. Making the gold coins was very profitable. Ormsby made four dollars for every twenty dollars he minted. Because the coins were debased, they did not circulate past the early part of 1850. To improve the issue, Ormsby hired Dr. William Light, a dentist. He was paid fifty dollars per day to correct the problem. However, he felt that he was underpaid and soon left the business.

There are only five J.S. Ormsby gold coins known today. Ormsby also minted tokens, which were given as a receipt for one hundred dollars worth of gold dust. For many years the Ormsby coins were thought to have been issued in 1850 because the only known piece had thirty-one stars on it, showing that California had already been admitted to the Union. However, in 1911, a five dollar piece was discovered that had twenty stars. The coins were made by use of dies and a sledgehammer, upon poorly annealed gold planchets.

Later John Ormsby practiced medicine in Sacramento, Sonoma County, Sutter County, and Marysville, California. He was also an Assemblyman in the California Legislature of 1857. In 1866, after being a miner in the Nevada gold rush, he moved to Utah where he died ten years later.

William Ormsby was the manager of the mint. He also established a stagecoach line, a hotel, and a real estate business. He was killed in a fight with Indians in 1860 at Pyramid Lake, Nevada.