Hello, i have a stone having 12 % gold in it .i crushed it and add nitric acid so that copper,silver and other metals can dissolve as i dont need them so i filtered the liquid and waste it and put the leftover in aqua regia and wait for 1 day after that i was left with small metal pieces cant understand what metal it is as it did not dissolve in aqua regia and looks silver and grey i am attaching the picture of it please let me know what it is, also it is non magnetic plus i have a problem in the evaporating process of aqua regia as i heat it at slow flame until the solution decreases to a significant level and pour hcl in it then repeat it and lastly did the same but this time with water after evaporating what left is light green substance having some black sponge type thing on it ( i thought that the black thing is the waste or something like that because i thought that gold chloride is always in a brown or dark brown or yellowish colour it was my mistake i think as i was unaware of it ) so i repeat the evaporating process by adding some water again but this time no sponge or something else out so i decided to redo the whole process again by adding some aqua regia in the same previous leftover substance and add an aluminium sheet in it and wait for another day after that i repeat the evaporating process hcl washed but this time what left is a mixture of dark green and black substance i am attaching its picture also please please guide me that where i am wrong and what i have to do now glad to hear the experts opinion i am new here and inexperienced i read alot on internet but when it comes to practical i am confused,stuck and frustrated by not getting the results i want please correct me.special thanks to all.
stuck in aqua regia process
- Thread starter awm
- Start date
Help Support Gold Refining Forum:
If the stone has gold in it aqua regia process may or may not work, and with most stones would not work, in fact attempting to extract gold from ore with aqua regia not only normally would not work but can be very dangerous.
Aqua regia is used for refining gold, very seldom used for recovery of gold from scrap metals.
With ore trying to recover gold using aqua regia would almost always be a very bad idea.
A stone or ore can be composed of many different elements, some of which can produce deadly gases (arsenic for example), many compounds of the ore even if gold is involved may not let the gold react with the acids or a leach, or may need a pre-treatment for any acid leach to the attack gold, the base metals may take gold back out of the leach if gold was put into solution, for any acid or basic leach to work some pre-treatment may be needed to change the composition of the ore for a leach to work, and base metals may have to be leached first so as not to interfere with the leach of the gold.
Ore can be composed of many different combinations of the elements, leaching may or may not be the best choice for recovery even with pre-treatment.
Every ore is different and may take a different process to extract the gold, or to may take different methods to get more of the gold from the ore, many times it may take experimentation to extract the gold even after the elemental composition of the ore is known through assaying and testing.
Some ores the composition of the ore itself its minerals may also effect a leach adversely as the chemical composition of the ore and the chemical composition of the leach can react chemically to dissolve gold where the leach may not be intended to do so or may make the leach ineffective.
pre-treatment and concentrating the ore is normally done in many processes.
Different ores types normally take different methods of processing.
12% gold in a stone is a very high amount of gold, almost unbelievable (not impossible for vein gold in quartz), just crushing and gravity separation methods may be the best choice.
With a sulfide ore flotation may be a better option of concentration.
Unless the gold is free gold, and can be removed and concentrated through mechanical means. Then without understanding the composition of the ore through assaying, leaching with most any leach is just shooting in the dark at best...
In ore just because the ore is not magnetic ( or its dust is not magnetic) does not mean there are not the magnetic metals involved, the composition of the magnetic metals involved can be of a composition making them non magnetic.
Aqua regia is used for refining gold, very seldom used for recovery of gold from scrap metals.
With ore trying to recover gold using aqua regia would almost always be a very bad idea.
A stone or ore can be composed of many different elements, some of which can produce deadly gases (arsenic for example), many compounds of the ore even if gold is involved may not let the gold react with the acids or a leach, or may need a pre-treatment for any acid leach to the attack gold, the base metals may take gold back out of the leach if gold was put into solution, for any acid or basic leach to work some pre-treatment may be needed to change the composition of the ore for a leach to work, and base metals may have to be leached first so as not to interfere with the leach of the gold.
Ore can be composed of many different combinations of the elements, leaching may or may not be the best choice for recovery even with pre-treatment.
Every ore is different and may take a different process to extract the gold, or to may take different methods to get more of the gold from the ore, many times it may take experimentation to extract the gold even after the elemental composition of the ore is known through assaying and testing.
Some ores the composition of the ore itself its minerals may also effect a leach adversely as the chemical composition of the ore and the chemical composition of the leach can react chemically to dissolve gold where the leach may not be intended to do so or may make the leach ineffective.
pre-treatment and concentrating the ore is normally done in many processes.
Different ores types normally take different methods of processing.
12% gold in a stone is a very high amount of gold, almost unbelievable (not impossible for vein gold in quartz), just crushing and gravity separation methods may be the best choice.
With a sulfide ore flotation may be a better option of concentration.
Unless the gold is free gold, and can be removed and concentrated through mechanical means. Then without understanding the composition of the ore through assaying, leaching with most any leach is just shooting in the dark at best...
In ore just because the ore is not magnetic ( or its dust is not magnetic) does not mean there are not the magnetic metals involved, the composition of the magnetic metals involved can be of a composition making them non magnetic.
There are many different ways to process ore, much depends on the ore itself, an assay will give you an indication if the ore has enough value to process, and will give you a starting place in finding a method to recover those values.
What else does the assay indicate, since it appears that some of the analytes (concentrations of other metals, minerals, etc) are missing due to the right side of the photograph being cut off.
rickbb
Well-known member
Slow down, study more. You cannot get want you want with a step by step guide from this or any web site.
You have a complex ore and you need to tailor a specific solution to what you have. There is no cookie cutter formula to hand out for you to use.
AR is not what you need to be working with on this ore. Set that aside before you hurt yourself or others with some exotic poison gas.
Just because the assay says there is gold does not mean it's "free" gold ready to be separated and refined with AR. It is likely bound up with other minerals and will need multiple steps to get a final product out of it.
You have a complex ore and you need to tailor a specific solution to what you have. There is no cookie cutter formula to hand out for you to use.
AR is not what you need to be working with on this ore. Set that aside before you hurt yourself or others with some exotic poison gas.
Just because the assay says there is gold does not mean it's "free" gold ready to be separated and refined with AR. It is likely bound up with other minerals and will need multiple steps to get a final product out of it.
I am unsure how they got the report of metals involved in that report, what it does not tell you is what all the ore is composed of.
That sheet is only somewhat helpful, but not what we need to determine what the ore you have actually is, or what processes you may need to go through, or the possible dangers involved to process for values.
It only shows some of what the ore may have contained or what the concentrates of the ore can be converted into (for example if the ore was crushed and panned for concentrates and roasted, or concentrated through a sulfide flotation and roasted or concentrated and processed by some other means which may have resulted in the concentrates which reported as oxides...
The sheet says concentrates from the ore were analyzed. and showed these elements or oxides of these elements.
What it does not show how the ore (Concentrates) may have been treated before the analysis if the concentrates from the ore, (was the small amount concentrates tested from tons of ore roasted ?)... which could have changed the composition of the copper bearing ore to give copper oxides in the concentrated material tested.
The raw ore or stone you have, can be of a different composition than that of the concentrates which were tested, it could contain arsenic, sulfide or other salts that if roasted could have been driven off in the process...
This seems to be primarily a copper bearing ore that does not narrow it down much, the copper oxide could come from many different sources of copper minerals especially if the concentrates were roasted, only a few sources of ore possibility's:
https://en.wikipedia.org/wiki/Copper%28I%29_oxide
https://en.wikipedia.org/wiki/Cuprite
https://en.wikipedia.org/wiki/Chalcopyrite
https://en.wikipedia.org/wiki/Tenorite
https://en.wikipedia.org/wiki/Tennantite
https://en.wikipedia.org/wiki/Chalcocite
https://en.wikipedia.org/wiki/Bornite
https://en.wikipedia.org/wiki/Covellite
https://en.wikipedia.org/wiki/Malachite
https://en.wikipedia.org/wiki/Tetrahedrite
https://en.wikipedia.org/wiki/Azurite
https://en.wikipedia.org/wiki/Chrysocolla
https://en.wikipedia.org/wiki/Spertiniite
A more complete assay of your ore would give you a much better idea of what you have, at this point you have a piece of paper that really does not tell you what mineral you have, it just shows what someone had in some concentrates (which could have been processed) that they had analyzed for a few components. How can you be sure the concentrates came from the same stone as what you have? If they were, did they ore concentrates undergo a process that changed the composition of the ore from its mineral salts to its mineral oxides?
Not really much to go on...
How many tons of this ore do you have?
How many tons of the ore were processed to get the concentrates that show the results on the paper you have. How were these tons of crushed ore concentrated, and or processed?
The paper you have may, or may not give much a reflection of what the stone you have contains, or what is possible to get from processing the stone you have.
I would be tempted to take a sample of that stone, crush it, and roast it, and melt it with copper shavings (of a known weight), with a good reducing flux composition (high in carbon), in a reducing flame or environment, to keep the copper from oxidizing, and to reduce the copper oxides of the ore to metal in the fluxed melt, then proceed to process the copper slug, parting the slug with nitric then process the remaining powders, in your aqua regia.
If you have access to tons of this ore then spend a little money and get a proper assay and go from there.
That sheet is only somewhat helpful, but not what we need to determine what the ore you have actually is, or what processes you may need to go through, or the possible dangers involved to process for values.
It only shows some of what the ore may have contained or what the concentrates of the ore can be converted into (for example if the ore was crushed and panned for concentrates and roasted, or concentrated through a sulfide flotation and roasted or concentrated and processed by some other means which may have resulted in the concentrates which reported as oxides...
The sheet says concentrates from the ore were analyzed. and showed these elements or oxides of these elements.
What it does not show how the ore (Concentrates) may have been treated before the analysis if the concentrates from the ore, (was the small amount concentrates tested from tons of ore roasted ?)... which could have changed the composition of the copper bearing ore to give copper oxides in the concentrated material tested.
The raw ore or stone you have, can be of a different composition than that of the concentrates which were tested, it could contain arsenic, sulfide or other salts that if roasted could have been driven off in the process...
This seems to be primarily a copper bearing ore that does not narrow it down much, the copper oxide could come from many different sources of copper minerals especially if the concentrates were roasted, only a few sources of ore possibility's:
https://en.wikipedia.org/wiki/Copper%28I%29_oxide
https://en.wikipedia.org/wiki/Cuprite
https://en.wikipedia.org/wiki/Chalcopyrite
https://en.wikipedia.org/wiki/Tenorite
https://en.wikipedia.org/wiki/Tennantite
https://en.wikipedia.org/wiki/Chalcocite
https://en.wikipedia.org/wiki/Bornite
https://en.wikipedia.org/wiki/Covellite
https://en.wikipedia.org/wiki/Malachite
https://en.wikipedia.org/wiki/Tetrahedrite
https://en.wikipedia.org/wiki/Azurite
https://en.wikipedia.org/wiki/Chrysocolla
https://en.wikipedia.org/wiki/Spertiniite
A more complete assay of your ore would give you a much better idea of what you have, at this point you have a piece of paper that really does not tell you what mineral you have, it just shows what someone had in some concentrates (which could have been processed) that they had analyzed for a few components. How can you be sure the concentrates came from the same stone as what you have? If they were, did they ore concentrates undergo a process that changed the composition of the ore from its mineral salts to its mineral oxides?
Not really much to go on...
How many tons of this ore do you have?
How many tons of the ore were processed to get the concentrates that show the results on the paper you have. How were these tons of crushed ore concentrated, and or processed?
The paper you have may, or may not give much a reflection of what the stone you have contains, or what is possible to get from processing the stone you have.
I would be tempted to take a sample of that stone, crush it, and roast it, and melt it with copper shavings (of a known weight), with a good reducing flux composition (high in carbon), in a reducing flame or environment, to keep the copper from oxidizing, and to reduce the copper oxides of the ore to metal in the fluxed melt, then proceed to process the copper slug, parting the slug with nitric then process the remaining powders, in your aqua regia.
If you have access to tons of this ore then spend a little money and get a proper assay and go from there.
Yes the small amount is tested around 100 grams and 60kg is currently in the stock of supplier but he said he can arrange tons for many years.i want to tell you about the ore it looks like shiny silver colour and when i started crushing it, it broke into pieces and those pieces have golden colour visible and also copper colour was visible and the picture attached in my post above of the leftover from aqua regia that grey powder or small silver metal pieces shines golden too.
Color golden or silver does not really mean much with ore, several types of fools gold can be mistaken for gold by someone not familiar with the difference of real and fools gold.
Crush and pan it, fools gold is light and will pan out of the pan easily, gold is heavy with its high density and will stay in the pan to the end (when panned correctly), silver is also fairly heavy and can be panned by gravity separation.
Fools gold is brittle and will crush easily, gold is softer and malleable which can be flattened.
At this point I would say the papers or the suppliers words are meaningless, you really have no idea if the paper is even for the stone you have, you have no idea if the sample stone you have is representative of the material he may sell you at a later date. He could have given you a cherry picked sample of good ore, or the best piece from a vein, to get you to buy a whole mine of mostly worthless rock, you need a good representative sample of the whole lot you plan on purchasing, and have a good assay done on the representative sample.
All you have is his word, a sample of concentrates that may or may not have come from tons of the processed ore (concentrated to a high value, from a large volume of more valueless ore), which may or may not be a representative sample of what he has to sell you, with a piece of paper that only tells a partial story, of what the concentrate may or may not contain if processed to a concentrate the way he processed it.
All you have now is enough to get you interested this may be something to peruse, without any education in mining you are likely to just be setting up yourself to loose a lot of money buying tons of worthless rock with no understanding of how to get any value from it.
You would need a lot of education to be able to proceed, and will have a lot of trials and errors to get it right. you will need to learn many different things, first you will need to learn how to determine if the ore has enough value. and how to recover those values, how to concentrate it and process it for further recovery, learning the best recovery method, and best way to process for further treatments, for that specific type of ore, and then how to smelt, leach, or get the values separated for further refining...
Just because a rock has gold, it may not be worth the time and trouble to get the gold out of it, and if it is worth it, you will need to be able to know enough of how to do it, or may have to experiment with your knowledge of many different methods to find a method to recover most of those values from the stone, not all rocks are alike, not all methods will work for different types of rock...
If you plan on proceeding with more than a small sample out of curiosity, get a good assay of the ore, that will give you a full picture of what you may be dealing with, example find out if this is a sulfide ore, an arsenic bearing ore...
Without the assay you really have no place to go, except to wandering around in the dark trying to find a way out, and possibly putting yourself in danger in that dark, or setting yourself up to spend a lot of money and time with nothing to show for it.
Without an education in mining, or skills in recovery and refining your still in the dark just wandering around looking for a way out of a mess.
Then you may not just be stuck in some aqua regia process, but you could be stuck with tons of expensive stone that is basically worthless, and no idea what to do with it.
Get the assay and work on your education, trying to get gold without these is just wandering around blindly.
Crush and pan it, fools gold is light and will pan out of the pan easily, gold is heavy with its high density and will stay in the pan to the end (when panned correctly), silver is also fairly heavy and can be panned by gravity separation.
Fools gold is brittle and will crush easily, gold is softer and malleable which can be flattened.
At this point I would say the papers or the suppliers words are meaningless, you really have no idea if the paper is even for the stone you have, you have no idea if the sample stone you have is representative of the material he may sell you at a later date. He could have given you a cherry picked sample of good ore, or the best piece from a vein, to get you to buy a whole mine of mostly worthless rock, you need a good representative sample of the whole lot you plan on purchasing, and have a good assay done on the representative sample.
All you have is his word, a sample of concentrates that may or may not have come from tons of the processed ore (concentrated to a high value, from a large volume of more valueless ore), which may or may not be a representative sample of what he has to sell you, with a piece of paper that only tells a partial story, of what the concentrate may or may not contain if processed to a concentrate the way he processed it.
All you have now is enough to get you interested this may be something to peruse, without any education in mining you are likely to just be setting up yourself to loose a lot of money buying tons of worthless rock with no understanding of how to get any value from it.
You would need a lot of education to be able to proceed, and will have a lot of trials and errors to get it right. you will need to learn many different things, first you will need to learn how to determine if the ore has enough value. and how to recover those values, how to concentrate it and process it for further recovery, learning the best recovery method, and best way to process for further treatments, for that specific type of ore, and then how to smelt, leach, or get the values separated for further refining...
Just because a rock has gold, it may not be worth the time and trouble to get the gold out of it, and if it is worth it, you will need to be able to know enough of how to do it, or may have to experiment with your knowledge of many different methods to find a method to recover most of those values from the stone, not all rocks are alike, not all methods will work for different types of rock...
If you plan on proceeding with more than a small sample out of curiosity, get a good assay of the ore, that will give you a full picture of what you may be dealing with, example find out if this is a sulfide ore, an arsenic bearing ore...
Without the assay you really have no place to go, except to wandering around in the dark trying to find a way out, and possibly putting yourself in danger in that dark, or setting yourself up to spend a lot of money and time with nothing to show for it.
Without an education in mining, or skills in recovery and refining your still in the dark just wandering around looking for a way out of a mess.
Then you may not just be stuck in some aqua regia process, but you could be stuck with tons of expensive stone that is basically worthless, and no idea what to do with it.
Get the assay and work on your education, trying to get gold without these is just wandering around blindly.
Panning doesn't work if the gold is included as microscopic inclusions in sulfides.
I've seen ore samples with arsenopyrite that contained 2500 grams per ton but wasn't visible at all. That mine never made any money.
A warning, roasting an unknown ore could be fatal. Our long time member Irons can attest to that. Roasting arsenic containing materials releases poisonous gas and smoke.
http://goldrefiningforum.com/phpBB3/viewtopic.php?f=44&t=10018&p=207114&hilit=arsenic#p207114
Göran
I've seen ore samples with arsenopyrite that contained 2500 grams per ton but wasn't visible at all. That mine never made any money.
A warning, roasting an unknown ore could be fatal. Our long time member Irons can attest to that. Roasting arsenic containing materials releases poisonous gas and smoke.
http://goldrefiningforum.com/phpBB3/viewtopic.php?f=44&t=10018&p=207114&hilit=arsenic#p207114
Göran
Hey i put the leftover in concentrated hydrochloric to attack titanium and zinc for a day after that i add hydrogen peroxide and hydrochloric the reaction was too nasty and then filtered it add urea to neutralize and sodium metabisulphite after evaporating some brown material came up,i am attaching its picture plus i tried to melt it through the fire gun which is used in repairing air conditioner and that brownish material turns into red hot metal piece it was too bright cannot be seen when heated after that it converted to black metal piece i am attaching its picture also.i think that gold doesnot melt properly due to some pressure and temperature problem please check it out and guide me in this regards thank you.
Attachments
Before you added SMB did you test your solution to see if there was any gold at all?
Göran
Göran
