Yavapai County Arizona Gold Production
The Peck district is in the drainage area of Peck Canyon and Bear Creek, about 20 miles south-southeast of Prescott.
Rich silver ore was discovered in the Peck mine in 1875, and in the following 10 years $1 to $1.5 million worth of silver was mined. Other silver deposits were found in the late 1870's. By 1885 the rich ore of the Peck mine was depleted, and work in the succeeding years was mainly by lessees. In the early 1900's copper-silver properties were developed which yielded considerable byproduct gold. From 1932 through 1959 the district was for the most part inactive. Total gold production from 1890 through 1959 was about 15,550 ounces.
The area is underlain by Precambrian rocks, chiefly the Yavapai Series, which here includes quartzite and layers of amphibolite, chlorite, and sericite schist. The belt of schist, about 2 miles wide, lies between areas of Precambrian Bradshaw Granite. Porphyry dikes intruded the schist parallel to its strike (Lindgren, 1926, p. 160).
The veins, found in the quartzite and schist, are parallel to the foliation. The rich silver-bearing veins contain a gangue of siderite or ankerite, which near the surface is almost wholly oxidized to limonite. The principal ore minerals are bromyrite and subordinate native silver, but locally the veins contain chalcopyrite and silver-rich tetrahedrite. The copper-rich ore bodies found in the De Soto mine are overlapping lenses of fine-grained quartz in the chloritic schist of the Yavapai Series. They contain pyrite, chalcopyrite, some sphalerite and galena, and sparse tetrahedrite and arsenopyrite (Lindgren, 1926, p. 161-163). Gold occurs as microscopic grains in the sulfides.
PINE GROVE-TIGER DISTRICT
The Pine Grove-Tiger (Crown King) district is in the heart of the Bradshaw Mountains 40 miles by road southeast of Prescott; the Tiger camp lies immediately south of the Pine Grove camp. The ores, which were very rich in silver and gold near the surface, also contained significant amounts of copper, lead, and zinc.
A few mines in this district were worked as early as 1874, but there is little indication of any significant development until after 1890. The Crown King mine, the most important gold property of the district, was most active between 1893 and 1900 (Lindgren, 1926, p. 168). More recent productive flurries occurred during 1903-23 and 1934-51. The total gold production through 1959 was about 130,275 ounces.
Bedrock in the district consists of Precambrian Yavapai Series and Bradshaw Granite which are intruded by a stock and dikes of granodiorite of Mesozoic or Tertiary age and by younger dikes of rhyolite porphyry and granite porphyry (Lindgren, 1926, p. 21-23, 164-176).
The ore is in veins which are most abundant in the granodiorite; a few extend into the surrounding rocks. The vein minerals are pyrite, chalcopyrite, sphalerite, galena, and some tetrahedrite in a gangue of quartz with a little ankerite and calcite. In some of the sulfide ore, native gold is present. Much of the mined ore was partly oxidized and rich in gold and silver (Lindgren, 1926, p. 164-165).