The Clark, Gruber & Company banking firm was established in Leavenworth, Kansas, in 1857 by Milton E. and Austin M. Clark (brothers), and E.H. Gruber. They opened a new branch house in Denver in 1859. Denver was in dire need of coinage. Most of the business transactions were conducted with gold dust and the purity of the gold was always an issue--was it 16 caret or 20 caret? The shopkeepers usually came out ahead in transactions with the miners. If the miner sent his gold back east for exchange he had to pay for shipping and by the time he got back his cost had brought the price lower than what the local shopkeepers would give him.
The privately operated mint was just what the miners and Denver needed. The building was located at 16th and Market Streets and started to produce coinage on July 20, 1860. They issued coins with their own stamp upon it, in denominations of $20, $10, $5, and $2.50. They had the best of facilities for assaying and designed to have their coins so pure that it would be worth par at the U.S. Mint.
The $10 gold piece displays on one side the American eagle and the words "Clark, Gruber & Co" near the edge of the coin, with the date 1860 in the usual place. On the reverse side is a picture of the "Peak" with the words "Pikes Peak Gold" above and "Denver" beneath. "Ten-D" (ten dollars) appears in its appropriate position.
The first year of coins came from unalloyed native gold. It was soon discovered that they abraded too easily and for the second year's production in 1861, an alloy was added to harden the coins for circulation.
On April 21, 1862, the Government acquired the Clark, Gruber & Company for $25,000. Unlike Clark, Gruber & Company, the Denver plant performed no coinage of gold as first intended. One reason given by the Director of the Mint for lack of coinage was, ". . . the hostility of the Indian tribes along the routes, doubtless instigated by rebel emissaries (there being a Civil War) and bad white men."
John J. Conway & Company started another territorial mint. Very little is known regarding the mint except that it operated in Parkville, Summit County, in the Summer of 1861. Conway & Company, jewelers and bankers, advertised to receive gold dust and coin it into $10, $5, and $2.50 gold pieces. An unknown quantity of such coins was produced at its mint.
Another short-lived entrant in the game of coining Colorado gold was Dr. John D. Parsons who, in partnership with a Mr. Black, formed Parsons & Company, setting up his assaying and minting equipment near Tarryall in South Park, Colorado. The coins are undated but the Weekly News of Denver and the Miner's Record issued at Tarryall carried news items in 1861 concerning the J. Parsons & Co. gold coinage.
The final curtain came down on private coinage with Congress' passage of the Act of June 8, 1864. This act intended to stop the minting of Civil War tokens and legislation prohibited the private manufacture of any coins designed to pass as money.