Tintic District History

100 Years of Land Consolidation

The Company’s Land & Mineral Ownership within the Historic Tintic District were once held by Chief Consolidated Mining Company (CCM).

CCM was founded in 1909 and by the early 1970’s had absorbed nearly a dozen smaller mining operations resulting in the consolidation of much of the Eastern Portion of the Tintic District.

During this 100+ years, tens of millions of dollars were invested in capital improvements – to include over 6 existing mines and over 20 miles of underground workings, thousands of pages of historic data and multiple facilities – that survive today on TCM property and that would have cost over $200 Million at current valuations.

 

Historic Production

In 1869, silver, gold, lead, zinc, and copper were first discovered in the Tintic district. By 1899, the Tintic Mining District was considered to be one of the richest mining districts in the entire nation, spawning hundreds of workings and dozens of high-grade producing mines. Ores are hosted in carbonate replacement lead-zinc-silver-copper deposits, and more discrete high-grade gold-silver quartz vein hosted deposits. Major production ended around 1978 due to low metal prices, fractured ownerships and poor capitalization. Prior to that the District had proven to be a prolific producer of Precious and Base Metals. The table below summarizes the Tintic District’s historic production at current metals prices:

 

Mining History

Ore in the Tintic District was initially discovered in outcrop in 1869. Within a few years, most of the major outcropping ore bodies were being mined and there were 15-20 exploitation and exploration shafts in production. By the end of 1871, three mining camps had been established – Eureka, Silver City and Diamond City.  As a result of the high-grade ores, shipments were sent long distances to smelters in San Francisco, Reno, Baltimore, and as far as Swansea in Wales.

Even though many claims had been staked in the eastern portion of the district before the turn of the century (now identified as the East Tintic District), the only occurrence of surface ore was a small outcrop of lead-silver mineralization near the present Eureka–Lily shaft. This outcrop was in an area of intense alteration of both sediments and volcanics. All future discoveries of major deposits in the East Tintic would be blind ore bodies, based on surface alteration, and found by underground geologic interpretation.

E.J. Raddatz around 1906 acquired a major holding in what is now the Tintic Standard area. Raddatz reasoned that there was a chance of discovery in the Ophir limestone at depth and in 1916 discovered the Tintic Standard deposit. The Tintic Standard Mine went on to become one of the major lead-silver mines in the world.

Mining geologists, attracted by the discovery of the Tintic Standard, began to study the district. Among these was Paul Billingsley, who in the early 1920’s developed skills that led to the framework for modern prospecting. He observed that the volcanic cover in the east was pre-mineral and was altered by various stages of mineralizing fluids contemporaneous with ore deposition. He also recognized that the dikes and fissures cutting the volcanics continued at depth into the underlying sediments. Based on these ideas, a long drive on the 700 level of the Tintic Standard Mine was commissioned. The target was projected from a surface exposure of a strong alteration zone, along with persistent dikes mapped within the volcanics. This exploration work intersected the ore deposit that became the North Lily Mine. Similar strategies led to the discovery of the Eureka Standard mine.

During World War II, the United States determined that new sources of raw materials were essential. As a result, the US Geological Survey spent 1942–1943 studying the East Tintic District. An exploration program seeking blind ore bodies was commenced and by 1945, four targets were defined. One of the targets was the CCMC Oxide area, centered on a prominent outcrop of oxidized and pyritized volcanics. However, no major discovery was made via the 75 ft (22.6 m) deep CCMC Oxide zone shaft.  Upon the subsequent discovery of the Burgin silver-lead-zinc deposit both Billingsley and the USGS were proven correct in their targeting of the CCMC Oxide zone.

District production slowly increased through discovery of new mines and peaked between 1921 and 1930, when according to data from the U.S. Bureau of Mines (Morris and Mogensen (1978), production for the decade from the combination of the Tintic and East Tintic Mining Districts reached 4,250,000 tons. From that peak, production decreased to a low of 662,000 tons between 1961 and 1970. Production from the Burgin Mine led to a second peak of 1,200,000 tons between 1971 and 1976.

Mining of the Trixie ore deposit began in 1969 and continued through to 1995, primarily direct shipping ore as precious metal-rich silica flux to Kennecott’s Bingham Canyon smelter.  The mine was re-opened for a short period between 2000-2002 aimed at exploiting high-grade gold ores from the Trixie Gold Mine’s 610 stope, but operations ceased due to the depressed gold price.