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can you use lye to refine gold from black sand

gold prospectors of the rockies - what to do with your gold

gold prospectors of the rockies - what to do with your gold

The simplest and cheapest way for the small-scale placer miner to retrieve the fine gold from the concentrates can be done in six simple steps. You will need a plastic gold pan, distilled water, household lye, an ounce of mercury, nitric acid, a Pyrex measuring cup, safety goggles, rubber gloves, and a rubber apron, a flat copper bar or sheet of copper, and assorted sizes of gold vials. You also may wish to use a miner's magnet. If you have a rock tumbler, you will need a piece of hexagonal steel bar that will fit into the tumbler or several stainless-steel ball bearings.

When you think you have enough of that fine flour gold saved up and you want to pour a "button," the following procedure works well. You will need a briquette of charcoal, some borax, and a propane torch.

WARNING! Some propane torches have a habit of flaring up a bit when you tip the flame end downwards. Be sure you have a low flame and that the propane bottle is at a lowered angle before placing the flame on the gold. A sudden flare-up at this point could blow your gold right out of the hole, so have it adjusted first.

Creating nuggets to make jewelry is just one way to double and triple the value of your fine gold. You will need a Pyrerx glass measuring cup, stainless-steel tweezers, and some sulfuric or Muriatic (Hydrochloric) acid (you can purchase sulfuric acid at some prospecting stores or at pool-supply stores).

One other note on black sands: Sometimes black sands carry values of gold that cannot be seen because of impurities or chemical bonding with a few other minerals, such as selenium and tellurium, which would have to be chemically broken down to reveal the gold. Silver is not silver-looking in nature, but rather a dark gray to black. Platinum has actually been dumped out because it wasn't seen. The best thing is to either take a well represented sample down for a fire assay, or do a chemical assay yourself. At the least, get a pestle and mortar (cast iron), crush a sample down to dust, and pan it out to see if there is any color there. But never toss away black sands unless you are sure it is void of ANYTHING of value. Actually, if you had a dozen 55 gallon drums of it, you could make a tidy sum of money!

instructions for silver refining using acid | shor

instructions for silver refining using acid | shor

Silver refining in acid is very simple, requires almost no investment in time, equipment or supplies and it can be done by almost anybody. However, it requires the use of concentrated acid and the fumes it produces are very corrosive. Therefore, it must be done out-of-doors, protective clothing should be worn and reasonable care must be taken.

It is best for the silver to have as much surface area as possible. That makes for much faster dissolution. So, if possible and convenient, melt your silver and pour it into the form of shot. Open-up granules are best. If gold is mixed with the silver, it is important that the gold be no more than 20% of the total weight. Otherwise the gold will interfere with the dissolving process. If you believe the gold content to be more than 20%, alloy down with copper to reduce the percentage of gold.

Weigh the silver and put it in one or more 5 gallon buckets. Add 150 ml nitric acid for every ounce of metal in the bucket(s). The acid will tend to react violently to the metal, bubbling and fuming. Make sure there is enough extra room in the bucket to accommodate the foaming (2-3 times, or more, the volume taken up by the silver).

When the acid stops foaming and all the metal appears to be dissolved. Pour off the acid ( filtering it if possible ) into another bucket or buckets. Do not allow any solids to be poured off with the acid or they will contaminate the final silver.

Add to the acid 1 ounce of SAC (silver precipitant crystals) for every 40 ounces of silver that is dissolved. As the SAC hits the acid, it will form a white precipitate (silver ) that will sink to the bottom of the acid.

Wash the silver repeatedly in water to remove any traces of acid. Add a couple of drops of aqua ammonia to the silver after your last rinse to test. If you see any color of blue, rinse some more. Use only a few drops of aqua ammonia. Ammonia not only smells strong, it can dissolves some of the fine particles of silver.

How to refine silver using baking soda, Karo pancake syrup, table salt, Red Devil drain cleaner and water: First dissolve your silver in nitric acid. You can do this in a plastic bucket but be sure to wear protective clothing like rubber gloves and to do it out of doors. When the silver is all dissolved, pour the acid into another plastic bucket. Be sure not to pour any particles along with the acid. Add ordinary table salt to the acid until the salt stops making white clumps in the acid. Pour off the acid. Add baking soda to the acid to neutralize it. Do not pour off the white "precipitate" that the salt formed. This is pure silver chloride. Rinse the silver chloride with water. To the silver chloride add Red Devil brand drain cleaner (lye) until all the silver chloride has turned black. Rinse with water. Add Karo syrup (dextrose) until all the black material (silver oxide) turns to pure silver.

how to refine gold by the acid method | shor international

how to refine gold by the acid method | shor international

The two acids which are used in this process are concentrated hydrochloric and nitric acids. Nitric acid is very corrosive. When combined with hydrochloric acid, the fumes become much more corrosive. So corrosive, in fact, that they will rust the highest grades of stainless steel with less than 1 second of exposure. For this reason, if you're using nitric acid, it must be done outdoors, away from anything that may be damaged by exposure to these fumes. If you're using a nitric acid substitute, it should still be outdoors, or within a self-contained system that neutralizes fumes.

Having described its hazards, it must be pointed out that, like most industrial processes, refining gold in acid is quite safe when performed under controlled conditions. In addition, the results of doing your own refining can be quite lucrative. Based upon feedback we've received from several hundred shops, approximately 6-10% of your gold profit can be saved by refining gold yourself.

For every ounce of scrap gold you are going to refine you will need a capacity of 300 milliliter. So, for example, if you are refining 10 ounces, you need a 3,000 milliliter (3 liter or 3 quart) container.

If you're using a nitric acid substitute: add 120 ml of hydrochloric (or muriatic) acid to the container, along with your substitute reagent. The MX3 will not have any effect until this acid is added. Hydrochloric (or muriatic) acid is available in most hardware, paint, or pool supply stores.

Usually, but not always, the acid reacts slowly at first. After some minutes have passed, however, the acid will become very hot and brown, very corrosive fume (nitric oxides and other fumes) will be generated. Wait a minimum of one hour after the fumes have disappeared before pouring off or filtering the acid. If you can, wait overnight. This will ensure that the acid has had sufficient time to completely dissolve the gold.

Do not add the mix so quickly that the acid foams out of its container. When the acid stops reacting to the addition of water/urea mix, stop. This will raise the pH of the acid from 0.1 To 1.0, neutralizing the nitric acid but not the hydrochloric.

There are many different selective precipitants that can be used when refining gold. All will do the job well. However, your local supply house has one or two that they may favor. We recently developed Quadratic Precipitant to overcome many of the problems that refiners commonly experience. For whichever selective precipitant you decide to use, follow the instructions that accompany the product.

Take a quart of water and heat it to boiling in a Pyrex or Visionware container. Remove it from the heat and add to the water one ounce of storm precipitant for every ounce of metal you are refining. If you are refining many ounces of scrap gold, you may need to use more than one quart of water. Do not put your face near the opening of the container. The smell is very strong and pungent.

Add the water/precipitant solution slowly to the acid. Immediately the acid will change to a muddy brown appearance as brown particles of gold form in the water. This brown "mud" is, despite its appearance, pure gold.

Testing is generally done with an aqueous mixture of stannous chloride, hydrochloric acid and pure tin. Generally it's more convenient to buy this premixed rather than concoct it yourself (see: ready-made detection liquid). The premixed is commercially available as Precious Metal Detection Liquid. Precious metal detection liquid will detect the presence of dissolved gold down to 4 parts of gold per million parts of acid, detecting the presence of about 1/1000th of 1 gram of dissolved gold. Testing for the presence of dissolved gold is absolutely necessary to insure that no dissolved gold is thrown away with the waste acid.

If any gold is still dissolved in the acid, the wet spot will turn a purple-black or a purple-brown. If you see this color change then give the precipitant more time to work and/or add more precipitant, and repeat the test until you determine that no gold is dissolved in acid.

When all the acid is poured off, add tap water to the mud. Stir and let the mud settle. Pour off the water into the container with the acid. If you have a filter, use it. Do not pour off any particles of brown. Repeat this rinsing 3-4 times or more.

If using a torch, first wrap the powder in tissue paper and then soak that in alcohol. We also recommend using a Burno crucible, to keep your gold from being blown away by the gas pressure of the torch.

If you had platinum in your gold, it will not dissolve, to any appreciable degree, in the room temperature aqua regia. It will be left behind when you pour off the aqua regia, prior to precipitation. To insure high purity of the platinum, you will need to re-refine this material. Put this material in a fresh aqua regia bath. This time, however, heat the acid to simmering. Continue heating until all the platinum is dissolved (that may take 1-2 hours). When completely dissolved at 1 ounce of ammonium chloride for every ounce of dissolved platinum. The platinum will precipitate as a red mud. If you want to leave the iridium in the platinum, then wait for it to precipitate before recovering the platinum. Iridium will precipitate as a blue-black mud after the platinum precipitates. Platinum group metals will also show up on the stannous chloride test. Platinum turns red, palladium. Palladium turns orange and iridium turn blue-black.

removing anodizing from aluminum quickly and easily. : 5

removing anodizing from aluminum quickly and easily. : 5

I dislike the color of many anodized parts and tools, and I love the look of bare aluminum. Fortunately, it's easy to remove the anodized coating from most things. I first heard about this here, but I found their instructions lacking.The pictures below show what we want -- and what we have.

You need:1. Some Greased Lightning Cleaner. 2. A plastic dish of some kind. 3. A brush. 4. Something with a coating that you just can't stand. I had a new folding knife which was a particularly nasty shade of olive drab.

If necessary, disassemble your knife/tool/object. You don't want to expose anything but the aluminum to the cleaner, if you can help it.Remove the spray cap of your Greased Lightning. Put your parts in your dish.Pour some Greased Lightning in there!

Scrub the parts with your brush. Constantly agitate the solution. Depending on the thickness of the anodizing, it may take a little while. My knife was HAIII -- which means that it has a thick layer of anodizing. It took about 15 minutes to get it totally clean.

Remove your parts from the solution using a tweezers or hook. Run it under cold water until there are no more suds. Pat dry with a towel or paper towel. Look at your clean, non-ugly parts. Great!Oh bother. Now you have to put the thing back together.

After reassembly (obviously only applicable if you first disassembled your object), check that everything works. I think this thing is dead sexy in white. And after almost a year of carrying, it still looks great.

It's been a while since I have used this method - it's likely that other "purple" cleaners will work. The key is that they contain a detergent and a small amount of sodium hydroxide (see my previous comments). Sometimes, you can get the info on ingredients from the SDS (Safety Data Sheet) or MSDS (Material Safety Data Sheet).

Thanks Daniel,Am having trouble finding Greased Lightning, plenty of other similar products.Some that I know would work because they contain Sodium or Potassium Hydroxide. However they go so far as to say Do Not Use on Aluminum. If exposure is limited to say 10 minutes then washed off, I'm thinking it'll be OK.I need to un-anodize four center caps off my aluminum/alloy wheels so that I can polish them to a mirror finish.The SDA or MSDS sheets might mention the Hydroxide but neither so on to state the concentration or percentage concentration.

I don't thing you removing the anodized surface. It looks like your just scrubbing the dye out of the anodized surface, as anodized aluminum has large amounts of microscopic pores and that's what enables it to be dyed so readily. The aluminum oxide(anodized surface) is harder than most steels (that's why its used in most grinding wheels and sand paper), albeit very thin, and scrubbing with cleaner and a brush would not scratch through it.

Hello, I am a chemist that works in a metal finishing shop and we anodize parts for aerospace and the military. I'd like to shed some light on this process but I would pose some questions and information first.1) why would you want to take the anodize off? Anodizing protects aluminum from corrosion. Without the coating, aluminum will corrode over time (white splotchy appearance) and will ruin the whole purpose of the item being used. If you don't like the color, why don't you buy a knife with the color you want? or without color? You can get anodized Items without a color and have them still be protected.2) Bare aluminum will protect itself from the environment by forming a very thin layer of aluminum oxide (which is the same component of an anodized surface) but that will hardly protect itself from corrosion.3) Stripping the anodize will also cause the material to change dimensions. When you anodize a part, the bare part will be a little smaller dimensionally before it gets anodized. The manufacturer does this on purpose because they know that anodizing will increase the thickness of the part evenly on all surfaces. Removing the anodizing changes its dimensions by making it smaller and then you will get other problems like..4) The sheath not fitting correctly and the hardware attaching the knife to the sheath not fitting correctly. The manufacturer designs the part with a very high tolerance (like within 0.0002") to make sure everything fits correctly. If the hardware attaching the knife is too loose (because you stripped the anodize) your knife blade might fall off when using it. Also, the sheath might not fit correctly and will cause the knife blade to be exposed to the environment which will cause the knife blade to corrode. All of these are bad. 5) From your pictures and notes you said it was "HAIII" which means it was Type III anodized or "hard anodized." Hard anodizing produces a harder more abrasion resistant coating than Type II anodizing ("regular" anodizing) but from looking at your pictures, the original sheath doesn't look hard anodized. Hard anodized coating will come out very dark. Depending on the alloy it will be dark brown or dark grey. Another issue is that hard anodizing produces smaller pores (look it up) that makes it very difficult to accept a dye color. Most of the parts we do here that are hard anodized will only accept a black color. Any other color makes it look weird. If the knife manufacturer said the sheath is "hard anodized" they are either lying or the coating is so thin, that its abrasion resistance will be the same as regular type II anodizing. That out of the way, if you still want to remove the anodize, the best way is to use a drain cleaner of some sort. Drain cleaners have sodium hydroxide (caustic soda) and/or potassium hydroxide. **CAUTION! THEY ARE VERY NASTY AND CAUSE BURNS!!** Be EXTREMELY careful when handling these chemicals. When immersed, the part will bubble vigorously. You probably won't need to scrub if the drain cleaner is strong enough, plus that could cause the chemical to splash and you don't want that. Once all the color is gone, if you just wanted to get rid of the color, you're done. Just wash off with PLENTY of water and dry it. If you want to remove all of the anodize layer, youre going to have to get a continuity meter/tester.The aluminum oxide of the anodized layer is an insulator. This means it does not conduct electricity. A continuity meter checks if there is an electrical current flowing through objects. Attach the part you're checking to something conductive like steel or copper or maybe a piece of aluminum foil (make sure they are both touching). With the continuity meter clipped to the other metal, touch the tip of the meter to the part. If the light turns on, there is current flowing to the part and all the anodizing has been removed. If not, there is still coating on it and you have to strip it more. You CANNOT re-anodize a part unless all the coating has been stripped off. You might be able to get the bare aluminum look (as opposed to the white above) if you polish the part again but usually it won't become bright and shiny again. Of course, you can always send it to a metal finishing shop and let the pros do it :)Sorry for the long response but I like to educate :)

I am looking for a way to remove the black and grayish coloring on some aluminum cookware that I simmered in plain hot water for a while to remove old dried food. Now I have another problem with trying to remove the black/gray areas (just in some areas of the thing aluminum pieces of cookware). Would a drain cleaner be appropriate or not. I don't want to end up with a rough surface after cleaning the black off.

Useful info, but sometimes it is necessary to get to the SOFTER aluminum below the anodizing. For example the mounting rings for a rifle's scopes can sometimes slide back due to the force of the ammo being fired repeatedly. If the anodizing is removed and then the rings are remounted to the rail they are less likely to slide back over time causing the scope to no longer be zeroed in. Small area of aluminum oxidization right at the connection may actually help to hold it better. Aluminum oxide Al2O3 is insoluble in water, fairly hard and useful stuff once it forms around the joint, not as attractive or good as the if you could Anodize it but good enough.

Hy SyedN2, unfortunately, aluminum is the hardest metal to plate on because of it's tendency to oxidize with the air (see point #2 above). To strip off the anodize, use the procedure above and you'll have to do the continuity test to make sure you removed all of the anodize. Time in the solution depends on how thick the anodize coating is. There is no real set time, it just all depends.

To replate, there will have to be some additional steps involved. The best method is to take it to a decorative plating shop and have them do it. They have the expertise to do it right the first time. Proper steps would be to clean/degrease the surface, deoxidize the surface using an acid step (50% nitric acid BE CAREFUL) and then the key part is you have to use whats called a "zincate" step. The zincate coats the aluminum with zinc hydroxide which protects the aluminum from the air so when it goes into the next tank, the plating will actually stick. After the zincate step it either needs a copper strike (thin copper plating layer) or an electroless nickel strike (thin nickel layer) you can plate the gold on top of the nickel.

I assume you wanted to try one of those home gold plating kits. I can assure you that they probably won't include the copper strike/electroless nickel strike or the zincate step. You can ask them if the kit can plate over aluminum but I would doubt it would actually stick. I would just take it to a plating shop.

Hello, I wish to buy a knife that is cheaper than its other versions because it is coated with a rainbow finish, would anodizing the blade remove this finish? And also is there a coating that I can buy in order to give it a finish of my own i.e. black? Thank you

Kind of figuring this out I build motorized bicycles and I stripped the emerald eyes off my bicycle frame and rims wet sanded and polished my aluminum looks like Chrome and the wax seems to protect it pretty well from what I read you saying that mind frame and rims will deteriorate

Just got a quick question for you. From what I could see in the picture, the brush didn't leave any scratch marks while removing the anodizing, but I still want to ask, did it scratch it at all? I'm working on something that I don't want scratches on. Hence why I don't want to use sandpaper.

One thing you can consider, is using a plastic brush, which will definitely be softer than any metal or anodized finish. I got a pack of plastic bristle brushes from Harbor Freight for a couple bucks. In my case it definitely didn't scratch it all, but to be honest, I barely needed the brush. I'm still using this knife-- it's in my pocket right now and the scratches on it are fro sloppiness, not from removing the anodizing color. Good luck with your project, please let me know how it turns out

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