History & Geology
All About Chalcopyrite
March 2017 by Chris Ralph
…there are loads of different copper minerals, but a large number of them form first in the ground as chalcopyrite and then through the effects of weathering are changed into other minerals like malachite, cuprite and chrysocolla.
Can You Recognize Valuable Ores?
The process of recognizing ores all starts with being able to recognize some basic minerals and knowing what hard rock ore looks like in the districts where you prospect.
The Ely Copper-Gold District of Nevada
The main ore deposits of the Ely district are associated with an east-west belt of altered and mineralized rocks measuring about one mile wide that extends 8 miles westward from Ely.
Eastern Arizona: Gold and Base Metal Deposits—Part I
Arizona is well-known for its copper-gold porphyries and massive base metal-gold sulfide deposits such that primary gold deposits in the state are often overshadowed.
Ask The Experts
Q: Is this gold or some other metal?
Placer Gold Deposits of New Mexico
While a large number of locations have yielded some placer gold, most of the state’s placer production has come from a few productive districts.
The Potholes—California’s Oldest Known Mining District
Every time we prospected here we found gold, sometimes some really coarse flakes, but no large nuggets (yet).
Mineralized Faults and Contacts in the Search for Gold
Fault zones and rock contacts are important because the vast majority of gold and silver deposits, as well as those of many other metals, are formed by hot, mineralized water solutions.
Subscription Required:
The Bawl Mill
• Ask The Experts: Can you review the differences in dry washers?
• Ask The Experts: Will this detector work for me?
• Ask The Experts: Nickel assays
• Ask The Experts: Potential for developing magnesite deposit
• Our Readers Say
• Selectable Frequency vs Multi Frequency Detectors
• Detecting Alluvial Bench Deposits -- Pt II
• The Goldfield Mining District -- Then and Now
• Nevada's Lithium Boom
• Old Patch, New Detector
• Over The Divide: James H Harrand & Daniel Yesberger
• Melman on Gold & Silver
• Mining Stock Quotes and Mineral & Metal Prices
