A few weeks ago I went out to check out some famous copper deposits in the Mojave desert. They are quite close to Los Angeles, but for some reason I had never gone out there to collect specimens. Having jet lag I decided to use insomnia to my advantage and get out into the desert before the sun came up and the temperatures start rising.
When I arrived I was greeted by this "fault" zone.
The fault is where one part of rock slides past the other part of rock and produces a semi-flat surface. Since each side is not attached to one another It allows the minerals to seep in. Various geologic forces, like hydrothermal, will push the minerals into the space between the fault producing an orebody. I am always amazed when I see these and think of the geologic forces that produce them.
This is the vein the miners were after.
Here it measures about 12" wide, but may have been larger. It was interesting that they left this behind, but sunk a shaft least 20' deep right next to this spot.
Luckily for rockhounds portions of the vein containing azurite and malachite were left behind. Even better, the tailings piles are littered with both minerals as well so there is little need to hard rock mine, you can just pick it all up.
(Malachite)
(Azurite)
(Azurite & chrysocolla)
An interesting side note, our bodies use copper for many things like making connective tissue and regulating the nervous and immune systems. The human body contains between 1.4 and 2.1mg of copper per kilogram. You won't get rich off of recycling humans for copper though.
This was actually the last stop during my long day out in the desert. Next time I'll show the other, much larger copper mine I went to.
Until then.....