(Some parts of Baja will remind you of gold areas in the U.S.)
In the first post of this series I introduced you the fact that good placer gold can still be found south of the Mexican border in Baja California. This includes both the northern half of Baja (Baja Del Norte) as well as the southern half (Baja Del Sur).
First off, let me remind you again you're going to need a highly detailed, topographic, or even a good historical map of Baja California, Mexico to locate many of the old mining areas I mentioned in my previous post and others that I'll mention along the way. I doubt a generic road map will be of much help in identifying these locations but you'll need one just the same to have a general idea of where you're going, especially if you're new to Baja.
Gold Geology of Baja
Although both the upper and lower (north and south) halves of Baja contain a centralized line of high mineralization that essentially extends from near the U.S. border in the north all the way to El Arco (southeast of Guerrero Negro in Baja Del Sur), this mineralized gold "belt" is not continuous. The biggest break in mineralization occurs about 30-40 miles northeast of the west coast town of El Rosario and extends to around Miramar (near the old Onyx mining area) on the east coast. (Note: My advice is that you avoid wasting any prospecting time in this "barren" stretch because better placer gold ground lies to the north and south.)
I don't know a lot about the gold geology of Baja Caifornia but I do know some geologists have compared it favorably to the central part of California in the United States, including the Sierra Nevada Mountains. Like parts of the Sierras, you'll find granite, schist, quartz (quartzite), diorite, and slate in abundance, especially in northern Baja. Although nowhere near as abundant as these country or host rocks, you'll also find lode and placer gold as well as other minerals and metals. This is especially true in Baja's northern half where I spent my gold prospecting and mining time.
Nearly all of Baja was subjected to severe tectonic activity millions of years ago with lots of volcanic action as well as much faulting, shifting, and folding of the earth's crusts. This is what caused much of Baja's mineralization back in the Cretaceous and Tertiary Periods. The key word here is Tertiary. If you don't already understand the importance of Tertiary gravels to gold placers you might do well to study up on the subject by reading Waldemar Lindgren's classic work, "The Tertiary Gravels of the Sierra Nevada of California."
In terms of Baja's visual prospecting clues that may lead you to the gold I'll give you this simple tip. If things look similar (to one degree or another) to what you've seen in gold areas in parts of Southern California (U.S.) and nearly all of the Motherlode Region in Northern California (U.S.), then you're probably onto something. Granted, Baja's overall terrain may prove alien to you, but I'm talking here about geological indications and again, visual clues. You savvy gold prospectors and miners out there know what I'm talking about. Enough said...
(Other parts of Baja will appear alien or foreboding.)
In my next post on gold in Baja California I'll start by addressing the nature of placers there and then provide you Baja's main mining areas and locations. Finally, I'll give you some personal insights based on my own experiences prospecting and mining in Baja Del Norte. Until then keep smiling and don't let the bastards grind you down.
(c) Jim Rocha (J.R.) 2013
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