Mineral collectors recognize the Collector’s Edge Minerals, Inc. of Golden, Colorado as one of the world’s premier sources for exquisite, collector-quality mineral specimens. Since 1984, the Collector’s Edge has operated numerous large-scale and small-scale mining projects, has purchased many significant private mineral collections, and has developed mine-direct sources for mineral specimens all around the globe.
While smaller projects came before it, our history truly began at the Sweet Home Mine in Alma, Colorado. On this page, you will find chronological information about the mine, and where, when, and how we discovered minerals and pockets.
You will also find information on other mining projects we have led throughout the years.
Announcing the permanent closure of the Detroit City Portal of the Sweet Home Mine
September 3, 2024
After 7 years of mining operations, the Detroit City Portal of the Sweet Home Mine has been permanently closed.
It has been a long journey for us on Mount Bross.
What in the world is going on up at the mine?
I’ll tell you, but I have to go back a bit. The last detailed update posted on the website was in May of 2020. There had been some personnel changes, the weather was rough, there was still tons of rock to move, though hopes were high after the last two...
The Mockingbird Mine, Mariposa County, California
Collector’s Edge Minerals, Inc. recognizes and thanks Rocks & Minerals for permission to use portions or all of their original article from “Rocks & Minerals”, Volume 83, Number 5, pp. 392-400. Contributing authors were Robert B. Cook, Department...
Red Lead Mine, Dundas Region, Tasmania, Australia
Collector’s Edge Minerals, Inc., through a partnership agreement with the owner, reopened the Red Lead mine in the Dundas Region, Tasmania, Australia in October 2012 to mine high quality crocoite specimens.
Red Cloud Mine, La Paz County, Arizona
In 2001 Colorado Calumet Co, Inc. (CCCI), acquired the Red Cloud mine from Wayne Thompson et.al. The mine is a small silver-lead deposit located in the arid and desolate southwest corner of Arizona, and CCCI worked the claim
Maynard Topaz Claim, Thomas Range, Juab County, Utah
Topaz has been found around the world. However, the Maynard Claim in Utah is known for its imperial sherry color, though not all are of this color. It can range from deep sherry to colorless, from gem quality to those
The Stoneham Barite Locality, Stoneham, Colorado – 2
Calcite at Stoneham ranges from pale yellow to deep honey-colored; solid, inter-grown layers tend to appear a deeper brownish yellow. Distinct crystals of calcite form rhombohedra, sometimes modified or distorted, and typically 2-4 mm in size.
The Stoneham Barite Locality, Stoneham, Colorado
Collector’s Edge Minerals, Inc. recognizes and thanks Rocks & Minerals for permission to use portions or all of their original article from the “Rocks & Minerals”, Volume 65, Number 3, pp. 202-222. Contributing authors were Peter J. Modreski, U.S....
Two Point Amazonite Mine, Teller County, Colorado, Part 2
Amazonite: K(AlSi3O8) Amazonite is a green microcline feldspar, with a hardness on the Moh’s scale of 6-6-1/2. It forms in the triclinic crystal system. Studies suggest that the color is the result of small quantities of lead and water in the feldspar. ...
Two Point Amazonite Mine, Teller County, Colorado
In June, 1997, a beautiful pocket of blue-green microcline (v. amazonite) specimens was discovered in the classic Lake George, Colorado amazonite mining area. The specimens were discovered 2 meters beneath the surface, inside a collapsed pocket, eventually...
The Wutong Rhodochrosite Mine, Guangxi Zhuang Autonomous Region, China
Collector’s Edge Minerals, Inc. recognizes and thanks the Mineralogical Record for permission to use portions or all of their original article from the “Mineralogical Record”, Volume 42, Number 6, pp. 521-544. Contributing authors were Bryan Lees and Steve...
Benitoite Gem Mine, San Benito County, California
Benitoite is one of the world’s rarest gemstones and possesses many unique qualities compared to other gems. It has a high index of refraction and a dispersive power that is higher than diamond, making the stone extraordinarily bright and fiery when cut.
The Sweet Home Mine, Park County, Colorado, USA
The Sweet Home Mine, in Alma, Colorado has produced many of the world’s best rhodochrosite specimens. It’s bright red color and gemmy interior place this mineral among the most desirable of all mineral species. The “Alma King”, and many other world-class specimens were discovered in this mine.
The Sweet Home Mine, Alma, Park County, Colorado – 2
Other Minerals: The Sweet Home mine rhodochrosite crystals have overshadowed reports of the other species from the mine (Caplan, 1936). Little information is found in standard mineralogical references. For example, two noteworthy species known from the mine,...