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.
A Journey Into the Silver Peak Range
The Gold Rush in California called hundreds of thousands of souls to leave their homes to journey to the the far reaches of the West. At first the rich goldfields of the Sierra Nevada beckoned to these adventurous pioneers.
Gold in The Midwest--Part I
Gold can potentially be found in all the glaciated areas of the Midwest, but to find it in any appreciable amount one needs to look to areas where the gold gets concentrated by more recent water flows.
The Birimian Greenstone Belts of West Africa
The country we were to visit was Burkina Faso, a small country about the same size of my home state of Nevada with about 10 times more people. The second day I was in Africa, we went out to the goldfields for the first time.
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.
Critical Minerals: Titanium—Part II
There are both hard rock and beach sand types of titanium deposits, but the hard rock deposits need to be at least 10 percent titanium while the beach sands often are economic with only two or three percent titanium.
Benches and Fossil Placers
Unfortunately for us mortal humans, we have a poor perspective on geologic time. When we look at a landscape such as a stream valley, we see it only in two, or at the most, three dimensions. We have poor comprehension of the valley’s fourth and most important dimension—time.
Metamorphic Greenstone Gold
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March 2024
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