Geology Reports⌕ Search
Home/Archive/USGS

USGS · cir567

Rutile and topaz in Precambrian gneiss, Jefferson and Clear Creek Counties, Colorado

Douglas M. Sheridan·Richard B. Taylor·Sherman P. Marsh
View original source ↗Read source document ↗Export metadata ↓

Abstract

Disseminated rutile and major amounts of topaz have been identified in Precambrian topaz-quartz gneiss northwest of Evergreen, Colo. The rutile occurs in quartz-topaz-sillimanite gneiss that forms a stratigraphic unit which is 11 to 100 feet thick and is identified along strike for more than 7,000 feet. Three composite chip samples taken across this unit contain 2.2 to 4.2 percent of rutile, by weight, in grains averaging from 0.1 to 0.3 millimeter in size. The topaz content, by weight, in the same samples ranges from 23 to 67 percent.

Explore related subjects

CircularReport

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Douglas M. Sheridan, Richard B. Taylor, Sherman P. Marsh. 1968. Rutile and topaz in Precambrian gneiss, Jefferson and Clear Creek Counties, Colorado. https://doi.org/10.3133/cir567

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related USGS reports

USGS2026

Coastal and Marine Hazards and Resources Program decadal science strategy 2020–2030

Overview The decadal science strategy of the Coastal and Marine Hazards and Resources Program (CMHRP) of the U.S. Geological Survey for 2020 to 2030 describes the CMHRP's vision and mission and the strategic framework needed to support key program goals: Conduct research and develop science-based tools that lead to safer, more productive coastal communities and improved stewardship of natural resources.

Circular↗
USGS2026

Coal beneath Federal lands in the United States—Mines, reserves, and resources

The U.S. Geological Survey (USGS) compiled a list of coal mines and tabulated the coal reserves and available coal resources beneath Federal lands in the conterminous United States. Coal resources beneath Federal lands in Alaska are also discussed in this report. In 2024, the 34 coal mines on Federal lands produced more than 261 million short tons of coal. Surface mining is used at 23 of the coal mines, and underground mining is used at 11. These 34 coal mines control more than 4.2 billion short tons of reported coal reserves. Most of the coal mines (31) and more than 98 percent of the reported coal reserves are on Federal lands west of the Mississippi River. Of all the States, Wyoming has the most coal mines on Federal lands (14) and produces the most coal from Federal lands. The Powder River Basin has the most coal mines per basin or coal field operating on Federal lands (12 in Wyoming, 2 in Montana). Most of the available coal resources in the conterminous United States are also west of the Mississippi River. There are five basins or coal fields in the West that each contain available coal resources of more than 25 billion short tons. The USGS estimates that more than 355 billion short tons of available coal resources remain beneath Federal lands in the conterminous United States. Alaska contains substantial quantities of coal resources. The USGS estimates that Alaska has at least 140 billion short tons of identified available coal resources but may ultimately have as much as 5.5 trillion short tons of coal resources.

Circular↗
USGS2026

2026–2031 U.S. Geological Survey strategy for a hazard ready Nation—Actionable science for risk reduction

Executive Summary The USGS Strategy for a Hazard Ready Nation provides an approach that U.S. Geological Survey (USGS) researchers and staff can use to deliver actionable, user-focused science that supports risk-informed decision making aimed at reducing risk and losses across the Nation. The Strategy builds upon successful efforts within the USGS and seeks to promote and prioritize similar work in the future under an organized framework. Rooted in four priorities—(1) center end-user needs, (2) enhance research relevance, (3) support product and service development and implementation, and (4) improve communication—the USGS Strategy for a Hazard Ready Nation is designed to focus and guide, not prescribe, activities. Strategic actions are proposed to achieve these four priorities in a timely fashion. The USGS plans to continually build upon the Strategy for a Hazard Ready Nation to deliver actionable information for risk-informed decision making.

Circular↗