GENERAL41483

• Permit No: M1995097
• IBM Index Class Name: General Documents
• Doc Name: BIBLIOGRAPHY WITH INTRODUCTION GLOSSARY OF TERMS AND LIST OF MINERALS
• Media Type: D
• Archive: No

xistorical Production
INTRODUCTION
The STEGEN REPORT 267 states that reported metal production
from the Aspen district through 1979 was 3,460 tons of silver
(3,140 metric tons or 101 million troy ounces), 294,200 tons of
lead, 11,000 tons of zinc, and 590 tons of copper. The
concentration of silver in the ores decreased and lead and zinc
increased with depth in virtually all the mines. Combined with
average grades reported by a number of writers through the years,
this information implies that the district produced about 4.4
million tons of ore with an average grade of about 0.18 silver, 88
lead, 28 zinc (not shipped in the early years but recovered from
ore and to a large extent from concentrator wastes later as the
pigment industry expanded), and 0.028 copper. The ores contained
approximately 168 barium.
The district itself is most commonly defined as extending
from the Richmond Hill-Annie Basin area to the south to the former
mining camp of Lenado to the north, a distance of about nine miles.
The vast majority of production came from an intricately
interconnected series of underground workings extending from
Tourtellotte Park to Hunter Creek, a distance of 3.8 miles, and
vertically from at least 2,400 ft. above the valley floor in
Tourtellotte Park, to 1,200 ft. below the Roaring Fork River in the
lowest level of the Smuggler mine, for a total vertical distance of
at least 3,600 feet. Thus most of Aspen's mining riches were
produced from an underground labyrinth carved out of only 1,658
acres, or 2.6 square miles. Probably somewhere between 59 and 108
of the rock in this total area, including ore, was actually
removed.
As previously stated, the likelihood of major new ore
discoveries in the immediate Aspen area, particularly in the
Leadville breccias, is small, although local pockets of high-grade
ore intertwined with old mine workings undoubtedly exist. without
known exception, ore value decreased with depth below the supergene
enrichment zone in both Aspen and Smuggler mountains. There have
been tantalizing hints, however, of rich ore in the Leadville
breccias at depth west of the current limits of the district, and
many non-traditional targets, such as brecciated zones in the
Manitou and Dyer Dolomites at major fault intersections, have been
inadequately explored.
Based on knowledge of the Aspen deposits inveterate
prospectors and mining romantics can tantalizingly speculate about
the possibility of sulfide ore at depth. For example, in the
vicinity of the Penny Hot Springs near Redstone, Colorado the
Leadville Limestone, almost certainly brecciated at its contact
with the Belden Formation, lies perhaps as shallow as 1,000 ft.
under the exposed sulfate-bearing Eagle Valley Evaporite in the
immediate proximity of major igneous intrusions (specifically Mt.
Bruce A. CO11105 - XXXl - SHUGGLER BIBLIOGRAPHY