34 miles outside of Rustic, Colorado. Access is very easy, but will require a 4WD. There is a Forest Service gate at the base of the canyon. As a claim owner you have a right to access through that gate. This will require a notice of intent with the Forest Service. Location is in the heart of the gold rich Manhattan district.

The Rockfield claim encompasses three adits that have all been gated. The lock systems are in good repair and will keep all but the most motivated vandals out of the mines. The historic reports speak of a 900 linear foot tunnel in 1901, intercepting a rich ore body that was returning up to 18 ounces of gold per ounce. The mine was shut down in 1941 by the war act. The mine was held by various companies and corporations, but was never re-opened for production. In the early 1980s, it appears that someone was stripping gold from the tailings with a trommel system and processing the tailings. There is a great canyon dirt road that leads to the claim. It could probably be run with high clearance AWD. and easily traversed with most any 4WD vehicle. There were no technical spots, just a few steep sections and tight roads. There is a large staging area below the mine with room for 6-8 vehicles. At the mine and around the mine there is room for another 8-10 vehicles. There are plenty of flats for staging equipment. This is a great site for truck mounted crusher and washer. Resources on the claim include lots of water in the creek on the claim, plenty of wood, shade and an old trommel that looks ready to work.

Alternate or previous names
Rodkfield, Pendergast Tunnel, Valentine Lod E, Matchless Nos. 1 and 2
Location accuracy 500(meters)

Analytical data
Milling ore from 1941 reportedly contained 18 oz/ton AU and 1.5 oz /ton AG.
Commodities:
Gold – Primary
Silver – Primary
Comments on the production information
Exploration and development from 1923-36; production in 1937 and 1 941; no production in 1938-40.
Comments on the workings information
900-FT crosscut tunnel and short crosscuts; surface trenches
Geologic Information
Ore body information
Thickness: 1.22M (4 feet)
Materials – Type of material
Pyrite – Ore
Host rock type: Metamorphic Rock- Gneiss Rock unit name: Metamorphic Rocks–Felsic And Hornblendic Gneisses;Laramide Intrusive Rocks–Quartz Monzonite Porphyry Rock description: Metamorphic Rocks–Felsic And Hornblendic Gneisses;Laramide Intrusive Rocks–Quartz Monzonite Porphyry
Deposit: airphotos indicate probable quartz monzonite dike trending N76 to 82E through metamorphics from N2 SE sec. 30 across N edge oF SW sec. 29 TO S2 S2 NE sec. 29.
Reference:
USGS Database – Rockfield Mine - http://mrdata.usgs.gov/mrds/show-mrds.php?dep_id=10014002

Discovery year: 1916
Discoverer: Carroll Alsbury (Pendergast Tunnel Claimant)
Previous owner/ operator: S. A. And W. T. Pendergast – Log Cabin – 1941
Year of first production: 1937
Year of last production: 1941