Where does it come from?
Above. Huge, heavily mineralized quartz ledge found while in search of the Motherlode. It's likely this has some good gold in it.
The age old question: "Where does it come from?" Men have spent their lives looking for the source of the gold. I've been hiking the remote canyons of the Motherlode for over twenty years now on the same quest. In all that time I've never seen so much as a footprint of one of these self-proclaimed environmentalists. For a bunch of people who claim they know more about the environment than I do, they seem pretty scarce in the outdoors. Then again I'm in some places where it takes some work to get to.
I spend a lot of time doing what may truly be called prospecting. Some think hopping on a club claim and running a dredge or highbanker but that's not prospecting. I'm never happy with the amount of gold I'm getting so I'm always searching for something better. For every hour I spend running equipment I likely spend double that looking for more gold. Not just more gold, but the source of the gold.
As you get older the canyons get steeper. It's an unalterable law of physics the distance up a hill is double the distance down a hill. There is probably some corollary which says the angle of descent is shallower than the angle of ascent, but I haven't worked out all the math on that one yet. I have measured (in footsteps) the distance down a hill and up a hill, and I can tell you they grow once you're at the bottom. They seem to reset once you're out of the canyon to avoid scrutiny by USGS map makers who may find it curious their topo lines keep changing.
It's just the way it is when you're prospecting.
Above. The same ledge, close up showing the degree of mineralization.
Most picture a prospector as a grizzled old miner with a gray beard, burro and a pick slung over his shoulder. That may have been true in the day, but now you're likely to run into a prospector with a GPS, digital map and MTRS plots of historic mining areas on an Ipad. It's likely he's got a $5,000 metal detector slung over his shoulder.
We prospect because we know the grass is always greener on the other side of the ridge. It's part of the drive which sends us deeper into the canyons looking for gold.
Long History of Prospecting
People have been searching for gold since, well before there were people. The Bible is filled with references to gold including the first mention of gold in Genesis 2:10-12 where the rivers flowing from Eden are described and the river Pishon is described as flowing around a land filled with gold.
The Hebrews had seven different words for gold depending on the type of gold it was and the Ark of the Convenant was commanded by God to be covered in gold.
A talent was a measure of currency used by the Hebrews which weighed 75lbs of pure gold. In today's dollars a single talent would be worth over $1.6 million so your time would be well spent prospecting for talents.
As far as I know the Hebrews didn't make it to California so the odds of finding a talent would be pretty long, but according to some the ancient tertiary rivers were the same rivers mentioned in Genesis. Some have even proposed the main tertiary river which extended from Argentina to the Klondike, and fed the California gold fields was the river Pishon.
When you're out hiking the canyons alone you give some thought to some of these theories. To be honest I've been pretty skeptical of it, but the more I think the more it seems plausible based on the lack of any other explanation. There are some curious finds in the tertiary channels which defy explanation such as the Calaveras skull, stone implements and the bones of mammals. They are curious because the tertiary rivers, or dead rivers, are supposed to be a minimum of 2.8 million years old. I've not heard a good explanation for how these artifacts ended up in the dead rivers at some hundred feet underground and underneath the lava caps.
The theories on the Pishon it would be hard to prove. Regardless, the ancient rivers carried an enormous amount of gold which they picked up from somewhere. Almost without exception the dead rivers carried enormous quantities of gold. If you want to read a good book on the dead rivers you can try "The Ancient River of Gold" by Raymond Wallace.
Wallace spent a lot of years tracing the path of the tertiary rivers through North and South America. He traced it from Argentina to the Klondike and claims virtually all significant gold deposits are the result of the ancient Pishon River. He provides the best description of branches and the main course of this old river as any I've seen. Whatever his theory on the source of the river he did a thorough job of mapping.
As prospectors we need to learn all we can about the dead rivers. They are the source of the majority of gold not just in California, but the world. Certainly there are significant hard rock deposits, and in the Motherlode there are lode mines and placer mines, but almost all the placer gold comes from the dead rivers. That still leaves the question - where did the dead rives pick up the gold? It has to be an enormous source.
I'm not looking for the tertiary channels, I'm looking for the source of the tertiary channels. A fool's errand to be sure, but can you imagine a better way to spend your time than hiking into canyons every day?
If the source, which had to have been a lode, was out there, and the proof is in the placer deposits, then that source must have been enormous. I've talked to some who believe the ancient rivers picked up there gold within miles of the placer deposit and they point to evidence that very rapidly the size of the gold becomes smaller. For example if you are above Downieville the nuggets are much bigger than if your are dredging near Bullard's Bar. If the source of the California gold was carried from Argentina it would stand to reason it would be nothing but flour gold with no nuggets.
Having considered this theory for some time I'm beginning to believe it. The proof is in the old hydraulic pits. The size boulder you see in the old channels indicates these rocks weren't carried very far. Perhaps the ancient rivers did flow between continents, and Wallace believes he has traced a single river that far, but if they did then they were constantly enriching themselves along the way.
If you've spent some time in the Motherlode then you know the canyons are filled with mines. Go to Alleghany sometime. The ridge is honeycombed with mines burrowing in on the lode. Alleghany had to have been, and I suspect still is, the richest gold ore body in the world. But, you wouldn't know it looking at the town. California laws have created an economic nuclear weapon which destroyed mining and Alleghany. The lode under Alleghany is certainly a source of some gold, but not the source of the gold from the dead rivers.
With today's technology it's much easier for us to prospect. We can see satellite imagery at the click of a mouse and we have the advantage of a hundred years of people tracing the tertiary channels. You can download for free USGS topo maps; you can find folio maps; historic mining district information and you can visit the County Recorder who holds over a hundred years of mining records.
When you start marking these old mines on a map you quickly discover they cluster. The locations aren't random. When you start mapping the clusters you find they follow fault lines. This begins to explain the source. It's obviously lode.
Above. Remnants of a miner's cabin near the collapsed portal of a quartz mine.
There is one small problem. The lodes we see today are just seems of quartz. The amount of quartz in the tertiary channels exceeds every known quartz seem in California combined. In other words there is way more quartz in the tertiary channels, and almost pure quartz gravel, than there is a source for the quartz, which becomes the puzzle.
Certainly there's a lot of new undiscovered veins out there. I know a guy who found one a few summers ago and is still mining it today. I've seen some of the gold coming from it, and it's pretty nice. The Motherlode is covered in veins. If you've spent much time out there you know they're everywhere. You don't know if there is gold in the veins, but if you're in the motherlode it's probable there is. The only way to know is drill it and sample it. It would be the rare quartz vein which didn't show some gold.
I'm convinced there is still a lot of gold out there. I'm just limited in time looking for it. It seems I continue to find more places which require more time to explore. My list just keeps getting longer. Every time I find an old mine, or a new vein I'm tempted to started digging. Based on what I've found so far I could spend 24 hours a day just digging if I only tried to reopen the old mines I've found. Every one is worth exploring, but the majority are going to require some real work.
Above. Another quartz mine I found, the track still looks pretty good, it looks to me like they planned on going further in, but quit.
I'm not Mining, I'm in Church
As Rober Service said "It's not so much the gold as the finding it." If you've been on the hunt you know what he means.
I'm continually perplexed by a State with such vast resources of gold which seems intent on stopping you from finding it. There seems to be a class of people who believe mining gold is a criminal act. If gold is good enough for God to put on the Ark of the Covenant, without restrictions as to how it was mined, one would think simply dredging it from a river wouldn't be a criminal endeavor. In fact, it may be a religous practice and the State is actually denying you the right to practice your faith. After all you're on the hunt for the river Pishon.