The coins made by Dubosq & Co. of San Francisco were struck from 1849 to 1851. Although once abundant in circulation, they are extremely rare today. The only known pieces are five and ten dollar coins that are dated 1850.

In 1849, the ship Gray Eagle sailed from Philadelphia and included Theodore Dubosq Sr., and his sons Theodore J., and Henry. On May 31, 1849, the Alta California carried this notice: "We learn that Mr. Theodore Dubosq, jeweler from Philadelphia, who recently arrived in the Gray Eagle, has brought with him the necessary machinery for striking private coins."

It is not known if Dubosq actually struck coins in 1849, however trial pieces for that date in copper are known. In 1851 Dubosq made $150,000 worth of coins dated 1850. When James King sent seven ten dollar pieces and three five dollar pieces to August Humbert for evaluation, it was favorably reported that they had an intrinsic worth of $9.93 and $4.96. After this information was published, Dubosq wrote to Humbert questioning him for not including the value of the silver content of the coins. He replied that he had not assayed the silver and considered it to be no more valuable than copper for his purposes because the cost of parting it from the gold was greater than the silver’s value. However, because of their high gold and sliver content, the Dubosq coins were melted in great numbers for their bullion content. The dies were kept and used by Wass, Molitor & Co. the next year.

An 1852 Wass, Molitor & Co. ten dollar gold piece was found on the shipwrecked S.S. Central America, which sank on September 12, 1857. The coin made with a Dubosq & Co. die.

An 1850 dated ten dollar splasher was sold at auction in 2008. The splasher, made from white metal, had a partial impression from the reverse die used to strike a Dubosq & Co. California $10 gold piece.