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Breccia Pipes
December 2001 by Edgar B. Heylmun, PhD
A breccia pipe, or chimney, is an irregular cylindrical mass of breccia that is often silicified and stands out as an iron-stained knob. They can be from a few feet to several hundred feet in diameter, and may or may not be mineralized.
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Geologic references for northern Nevada
Legislative and Regulatory Update
• Trump cabinet forming
• Last minute regulations
• California suction dredging
The Rocks That Burn: Is Oil Shale the Answer?—Part I
The day is old in the Rangely Oil Field in northwestern Colorado. I’ve paused in my southbound trip to take a gander at this historic field, one of the largest in the state. Intricate pipelines funnel water and carbon dioxide to the source rock far below.
Lease Issued For Potential Mine Near Mount St. Helens
A hardrock minerals lease and environmental assessment issued recently give Idaho General Mines the right to apply to explore property near 5,400-foot Goat Mountain, north and east of the Mount St. Helens National Volcanic Monument.
The Forms of Crystalline Gold
The largest and most perfect single gold crystals are nearly always in the form of octahedra. These large octahedral crystals often possess deeply recessed faces.
Hard Rock 101: Micro Blasting
Micro blasting can be used to take down hanging rock, separate minerals from overburden, and collect gemstones and other high-value product with minimal damage.
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