Friday, September 16, 2016

It's a Crazy Thing

 (These grasslands near Hughenden, Australia [minus the distant heights) remind me of the Victoria goldfield areas I mention in this post.)

Some gold-bearing zones or areas don't always display the visual clues we're used to seeing out in the field. I'm reminded here of the Cripple Creek gold strike in the U.S. state of Colorado in the late 1800s as well parts of Australia, with certain locations in Victoria Province coming to mind. Additionally, some gold-rich areas of Mongolia might fool the uninitiated who are used to certain visual signposts when it comes to gold. I'm sure there are many other such gold-bearing locations scattered throughout the world.

Subtle References

What are the typical visual signposts in both wet and dry placers? The list is long but includes visible evidence of mineralization in the rocks or along the high points (mountains, hillsides, terraces, etc.) surrounding an area; elluvial float or ore scattered about; blow outs or veins protruding above the surface; shear zones where diverse geological boundaries meet; evidence of previous sampling or mining; changes in flora; and so on ad infinitum. Non-visual clues can also be found in low-lying areas such as gulches, washes, arroyos, creeks, streams, creeks, and rivers where traces of gold can be found by sampling. This is the norm for most of us but some gold-bearing areas don't exhibit any of these visual or non-visual clues...at least not at first glance. Only a well-trained geologist or highly experienced and knowledgeable miner or prospector would be able to discern the subtle references to the existence of gold in such areas and history has proven that fact out.

An Example

Let me give you an example of what I'm talking about here. There are small commercial mining enterprises actively working areas of the old Victoria Province goldfields as I write this post. I've seen both photos and videos of more than one of these operations in Australia and I have to admit I was dumbfounded by the overall lack of ANY of the visual clues I've already mentioned in these locations. No mountains or existing heights of any sort, no creeks or streams or washes, no blow outs or veins, and on and on. As a small-scale guy with over 36 years of field experience I have to admit I am intrigued by these sorts of gold-bearing locations and I find myself asking just how the hell anyone would know gold was underfoot without the benefit of prior knowledge (geological or otherwise). At one location I'm familiar with in Victoria from a second-hand standpoint all that can be seen for miles (or kilometers if you're an Aussie) is flat-looking table land stretching off into the distance with a few scattered stands of eucalyptus scattered about but not much more. Yet 10-25 feet (or in certain instances at much less depth) underneath these flat lands lie ancient creeks and streambeds rich in placer gold, including much coarse gold and nuggets weighing as much as two kilograms (64 troy ounces give or take a little). Some of these gold-bearing watercourses were laid down as far back as 35 million years so the placer gold within them is ancient in nature...in fact twice as old as some of the placer gold I've mined here in New Mexico. Now I'm not trying to say that every gold-bearing area in Victoria is laid out like the table land I'm mentioning but at this particular location it's exactly that.

 (Four kilogram nugget from the Victoria goldfields.)

Gold Beneath a Mountain Meadow?

These things said, most of us would walk right over this ground telling ourselves that the earth we're treading is shit from a gold-bearing standpoint. Therein lies the bugaboo. Ma Nature doesn't always play fairly with us and what looks like barrren flat lands hides the fact that eons ago that area was highly active from a geological standpoint and also highly mineralized. Rivers and streams once flowed in these areas and large amounts of gold found their way into them to lie dormant as that same gold and the streams that bore the yellow metal were eventually covered up by tons of overburden caused by upheaval, shifting, erosion, and myriad other geological and climatic processes. The huge lode gold strikes at Cripple Creek, Colorado were primarily found beneath ground that had all the appearance of a mountain meadow surrounded by hills, with few (if any) visual clues to the presence of gold there. Yes, gold was found much farther down and away from the main lode area at Cripple Creek in existing watercourses and in this case it left prospectors and miners scratching their heads trying to determine just where that gold was coming from. Eventually they found the source(s) in those seemingly innocent mountain meadows Ive already spoken of and the Cripple Creek rush was on.

 (Old lode mine at Cripple Creek, Colorado.)

Betraying the Secret

Both large-scale and small-scale placer gold operations dominate large portions of Mongolia these days and have for some years now. Again, the landscape in and around many of these gold-bearing locations is exactly what you'd expect Mongolia to look like. Wind-swept steppes covered in short grass and small, undulating hillocks that contain little in the way of large flora or streams. Yes, there are some small gulches and washes that might betray the secret that gold exists there, but these are few and far between as far as I can tell. Yet beneath those steppes lies gold in large quantities, much of it derived from ancient geology and topography. Many true Mongolians have abandoned their nomadic lifestyle in favor of digging dangerous vertical pits down through the steppe to reach the gold laid down eons ago when those steppes didn't exist or were unrecognizable from a modern standpoint.

 (Small-scale gold miners working the Mongolia steppes. Does this look like good gold ground to you?)

The Masquerade

So what's the point of all my drifting here? To tell the truth I'm not really certain of that myself. What I am certain of, however, is that none of us help ourselves by having tunnel vision when it comes to the "common" visual clues related to the presence of placer or lode gold. By saying that do I imply you should move to Kansas or Nebraska (both great states but not much for gold) and start mining those plains filled with corn and wheat? Of course not. You always have to go where the gold is or where it's been found. But sometimes finding it isn't as easy as you think, especially in those areas where Ma Nature has orchestrated a geological masquerade to fool you. However, at the Victoria locations previously mentioned, once you've cut down into the earth beneath those table lands many of the visual clues we depend on to find gold become readily apparent, including heavily iron stained rock and earth, clay layers, cobble and gravel, and so on. Oh, did I mention gold and lots of it? Sure, Ma Nature can play games and hide her treasures well. But once you've broken that code those visual clues leading to gold start re-appearing in one way, shape, or form.

It's a crazy thing and I'm still pondering it.

(c) Jim Rocha (J.R.) 2016

Questions? E-mail me at jr872vt90@yahoo.com

4 comments:

  1. There's gold in them thar flats......?
    Somehow that just sounds "wrong"!! Interesting though. I guess like they say, "Gold is where you find it".

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  2. Great post. Living in Oklahoma after many years of Alaska and California is a little dim in the gold arena but will get out west soon. Thanks JR

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  3. Thanks for commenting Jack and you're welcome.

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