hmmmm, as if I do not bring enough "interesting" rocks home, lol!

Somewhere near 1/3 dwt in a lemon size quartz.......even for a huge lemon, I really hope he or someone else finds the source for that one.

Yeah Arthur. I was considering that. I may research that video more and see if I can scope even an approximate location. Seems to me if you followed the watercourse up, the fact that that river is hosting solid quartz riverstones with a goodly amount of gold means that that water somewhere upstream is cutting thru a deposit of lode gold?

It would seem to reason that way...

Hm. Went and re-watched the video. Still trying to learn to estimate placer gold weight by visual estimate, so looked at pictures of nugget and flake gold equaling 1/2 gram. I think I'm off a bit: https://www.youtube.com/watch?v=QFSLLjc27h8 But still, it was a decent amount of gold for the effort and no doubt some was lost to the t-shirt.

A couple of years ago, I had two ore crushers made by a welder to crush quartz from the Llano river area at Long's fish and dig. Simple long pole mortar and pestle style crusher made from solid steel. Worked a treat to powder that quartz. I doubt I lose anything in them unless the gold flattens out and bonds to the bottom?

Haven't used them enough to determine that.

I always try and find a quartz rock to bring home on every outing
I put them in my rock garden
Have never crushed one
I do want to pass a metal detector over them some day
One never knows, I could be sitting on a gold mine LOL

Bill

Occasionally I have friends bring me rocks from areas they go exploring, a lot of which are old mining tailings. If anybody tells you this is not worth the time they are lying, I have found substantial gold and a few pickers, not to mention other semi-precious stones by doing so.

My technique is to take the rock and place it in two heavy duty ziplocks and then place it on a anvil and hammer it until it is in small pieces. Small debris will come out of the bag as the hammering process create holes, just place something under the anvil that acts as a catch cloth. Once the rock is reduced to ruble I use a Iron Mortar and Pedestal to grind it down further. Once I have it all reduced down to a powder I pan it.

Though this is a bit of work I have thought that if you just reduce the rocks down to gravel size you could then add them to a tumbler and let it grind them down for you and then pan the outcome, less work but a lot more time.

Make sure you wear eye protection!

I was always a bit puzzled by this.....if there is any pickers of smaller pieces of gold in the rocks....arent they gonnna be reduced to powder or small and smaller pieces? Essentially grinding good gold away?

Also...did you ever run across obsidian that sounded strong with a metal detector? I have several pieces, tennis ball sizes that do this. I would never think that obsidian would have any traces of hot rock or iron in it? I never yet tried to crush them, but entertaining the thought.

As far as I know, gold does not pulverize. Might get bent up a bit but should stay together when the rock is being hammered apart. Remember, 1 gram of gold can be pounded flat to (iirc but I might be misremembering) a 9" square sheet.

I've crushed quarts and found specs of gold not visible in the rock and not detectable by the rock. I've crushed many, many more quartz rocks that had nothing. I've never found anything to justify the two sore elbows.

Cleaning the mortar, pestle and pans cab prevent some "misreadings." A couple months ago a crushed a specimen and panned it in a pan that had some gold in it, so it really skewed my results. I thought I had a vein worth mining, but going back to the area revealed no more gold. Closer examination of the gold made it look like it had not been pounded on with an iron mortar and pestle, so it turned out the pan I used, I had forgotten to put some gold in the vial before I put the pan away.

A Doctor friend was over last night for dinner and he brought several chunks of quartz/rock combo tailings that were rich with gold, he packed them down from a claim at 13,500ft elevation. I noticed two types of gold in the rock, there was the kind we normally look for, the nice shiny stuff, but there were huge amounts of globular brown rock that are about 86% gold. The quarts veins going through the rock are amazing, and many pocket geodes in some of them. I will be careful how I crack these rocks and when done panning I am going to setup a small leaching tank, now that is going to be a challenge.

Because a friend of his bought this claim he has endless access to the mine and tailings for about 3 months out of the year, that and if the altitude don't kill you, it looks like he stumbled upon a area rich enough to turn a nice profit. I have to admit I was very caught off guard by the size of the gold embedded in the rock and I am only looking at the surface.

This leaves me with a question? Is it best to pulverize the ore, remove the large and flaky gold, then treat with acid to dissolve rock, and then to leach the material? Pulverize and crushing gets what is visible out but much of the residual you cant see, do you acid treat that first or just go straight to leaching? Judging by the grade of this ore I wish I had a 55 gallon barrel sized tumbler but my neighbors would have us thrown out for the noise.

If you have left over black sands that you have already processed all of the gold out of try this experiment. Take those sands and put them in a acid proof plastic container, very carefully pour in Muriatic acid and let it sit for a day, make sure you do not cover and leave it outside. Rinse with water the next day and repeat another day and maybe another. Rinse with water again and take what is remaining and dry it out. Once it is dry re-pan it, you will be amazed at the amount of gold you missed.

Otherwise, take your left over sands and add them to your rose bushes and grapevines, they love the extra nutrients and literally triple in size the next year.

Benjamin,
You may want to reconsider crushing some of those. Attractive quartz rocks with visible gold can often be more valuable as specimens so worth more as is than the weight of gold that is in them.

    Benjamin, there are many opinions as to how to separate gold from rock and the steps involved can also vary depending on the composition of the rock / ore.  If you have free mill that can be gravity recovered after crushing, why leach it?  After all, that is kind of like taking a dollar, changing it into pennies and then back into a dollar again. 

 

    You might consider roasting the ore after crushing it to drive off any sulfur ( sulfides ) and / or chlorine ( chlorides ) thus changing the ore into an oxide before smelting or leaching it.

 

    As far as building a leach tank goes, I just use 5 gallon plastic buckets for processing noncommercial amounts.  The 5 gallon buckets are much easier to work with than 55 gallon plastic drums or larger tanks in my opinion.

 

    There is a lot of leaning involved when it comes to leaching and smelting, so do your homework.  I have been leaching and smelting now for about 15 years and still learning new techniques.              Ron 

HI Benjamin

All of the processes eluded to by others is spot on, the important thing is to do them in a specific order. Specimens that have solid veins of gold through solid rock may be more valuable if cabbed and the upper side of the rock dissolved from the gold veins. Have seen results never did it and not sure what is involved but results can be unbelievable.  There will be gold in the dissolved solutions afterwards. The crushing and collection of free gold is next. The following processes and the efficiency of them would depend on the make up of the rest of the ore, for example how much iron is associated with it. Certain minerals have negative effects on certain solutions in leaching. All of this is said with the NOTE that anyone working with chemical solutions or smelting needs to first learn all safety precautions to prevent injury and unintended results. I would suggest reading a lot on each operation you intend to perform and not just on internet but from reliable books available in library. 

     Yes Walter safety is foremost when using chemicals and working with molten metals.  Skin, lungs, eye protection, training and a good understanding of what can go wrong is important for ones personal safety.  Even breaking rocks requires safety equipment, such as SAFETY GLASSES for starters.

     You are right about reading well written books ( homework ) on this subject and to be careful of what is on U-Tube.

     When working with an ore that has many elements ( complex ) , I send it in for a X-Ray Spectrometer Analysis. This way I know if there are elements such as Arsenic, Mercury, Lead or other dangerous elements.  This also gives an idea as to what steps I will take to separate the " Nobles " from the " Junk Metals ".

     In any event I use the same safety precautions no matter what type of ore I work with, SAFETY FIRST!!!        Ron 

Hey Walter,
Thanks for mentioning Cabbing quartz with visible gold. That would be pretty, especially made into pendants or bolo ties! Due to mine and my families love of rock hounding, I've been considering buying my sister a cabbing setup with a rock saw. I'm currently on the lookout for a used setup in good condition.
Cheers!
Mary

Maybe a little different topic but I'll ask anyway. QUARTZ! I've been in area's that have pretty white quarts, and some area's that have different colors or smokie quarts. Why the difference and what could that mean as far as the geology? The area I've been playing in has area's with flakes and some wire gold. Most of it fairly small. A couple area's have white quarts, but I got into a spot last weekend that had a bunch of smokie quarts. I haven't crushed any yet but plan to bring some out next trip. Can you guys help me a bit on what I might be looking for? This smokie spot seems to be very specific on the hill too? Not scattered around?

Jim.
Quartz color is influenced by the underlying minerals. For instance, the amethyst (purple quartz) in South Carolina is found above Manganese deposits. Citrine (yellow quartz) is found over iron deposits. Not sure about smoky quartz but I'm sure someone here knows.

This may alter your perception, I go through places where crushed rock has been spread out and pick up the Quartz and I was made fun of by a friend, they said there is no gold in that parking lot or even in this area, Guess what I said yep and never mentioned gold I already have, he calls me a fool guess that makes what I find the fool's Gold. I just have to find where that Quartz came from every Quarry has a club that comes through looking for fossils, maybe I can get them to let me clean out the rock crusher underneath it on those week ends.