OK so today’s question comes from Griffin. Now before we get into the question, just let me say I have received quite a few of these similar type questions as Griffins and I never really thought about why; until just now. Here is his question:
Hey Gold Party LLC! I was wondering if I could do both parts of the process myself. I could buy the scrap gold and then refine the gold myself so I can skip sending it into a refiner and just do the entire thing for my own business.
Now my canned response to these has always been something like: Sure this would be possible, but not very probable. Doing the refining is a very expensive and messy process.
But something caught my eye today. I saw a video of a man melting down some scrap gold in a small crucible and simple set up. Here just watch the video for yourself.
Now personally doing all that is really not my cup of tea. I mean if you like working with high voltage and burning red metals, then hey that all good. Not my idea of fun. But I realized how easy the process looks on the video. I also realize that I have seen videos like this hundreds of times and never connected the possible confusion with the video content and the question.
So lets get one thing straight right now. What that man is doing is not smelting gold, but melting gold. That is right, there is a huge difference in the two. And that is where I think this question stems from. I can see someone seeing a video like this and thinking to themselves that this could be done. They could do something like this in a small warehouse or better yet down in their basement.
But let us stop right there and say no!
There is a big difference between melting down some gold and smelting the gold.
Melting gold is what you see on the video. You heat some scrap inside a crucible until it liquefies. You then take that liquid gold and pour it into a cast to make yourself a nice bar. And here lies the problem, the bar is only going to be as pure as the gold you put into it.
Yes we all know that gold jewelry comes mixed with other metals. It needs this mix to create enough strength to keep the jewelry from breaking easily. So roughly:
- 22K means 92% gold and 8% alloy
- 18K means 75% gold and 25% alloy
- 14K means 58% gold and 42% alloy
- 10K means 42% gold and 58% alloy
(please no emails to tell me my numbers are not exact…I said roughly)
So what exactly will you get if you melt your gold in a crucible like the man in the video? You will get a scrap gold bar of some percentage in the middle of that chart. What you effectively did was exchange one form of scrap for a different form of scrap. Or in other words…..you wasted your time.
Smelting gold is a whole other animal. Yes you are going to have to melt your gold in a crucible just like the man did in the video. Then you are going to have to call in a chemist. Because now you are going to have to extract that alloy out of your red hot melted gold. I doubt you are going to want to stick your hands in there to get the alloys out. And you are going to have to extract it to the point of leaving it at 99.99% at a minimum and 99.999%(yes that is 3 nines) preferably.
So how are we going to do this?
How about the easiest way to smelt gold?
So tell your chemist to bring an oxidizing agent such as Sodium Nitrate. We can mix that in our crucible and that will lock the alloys together so we can extract them easier. Again unless the scientist wants to reach his hand into the molten metal, we are going to need to extract it chemically. Silica will dissolve the alloys out for us just fine. And that is a pretty abundant material.
So there we are done. What did we get? If we were lucky? Maybe 93%. I suppose if we really practice we may get to 95%. Ouch not much better then 22K scrap. That is not going to work.
Miller Process For Gold Smelting
OK how about using the Miller process? Sounds like a good idea. Lets check on how this is done.
The Miller process is an industrial-scale chemical procedure used to refine gold to a high degree of purity (99.95%). It was invented by Francis Bowyer Miller. This chemical process involves blowing a stream of pure chlorine gas over and through a crucible filled with molten, but impure, gold. This process purifies the gold because nearly all other elements will form chlorides before gold does, and they can then be removed as salts that are insoluble in the molten metal.
Well using chlorine gas sounds a bit dangerous to me. And I can’t be bothered if I only get 99.95% pure. I cant even sell that for much more then scrap prices. What is a more common method for better purity?
Wohlwill Process For Gold Smelting
The process was invented in 1874 by Emil Wohlwill. This electrochemical process involves using a cast dore ingot, often called a Doré bar, of 95%+ gold to serve as an anode. Lower percentages of gold in the anode will interfere with the reaction, especially when the contaminating metal is silver or one of the platinum group elements. The cathode(s) for this reaction are small sheets of pure (24k) gold sheeting. Current is applied to the system, and electricity travels through the electrolyte of chloroauric acid. Gold and other metals are dissolved at the anode, and pure gold (coming through the chloroauric acid by ion transfer) is plated onto the gold cathode. When the anode is dissolved, the cathode is removed and melted or otherwise processed in the manner required for sale or use. The resulting gold is 99.999% pure, and of higher purity than gold produced by the other common refining method, the Miller process, which produces gold of 99.95% purity.
Uggg! They did this in 1874? I am not going to be able to set this up in my basement. Plus I am going to have to do that first method just to get to the 95% purity bar I need to begin the Wohlwill process. That is not very feasible.
So as you can see, even though it is possible to smelt your own scrap gold, it is not probable. To make it even worth your time, you would need to step it up to smelting many pounds of scrap gold a day. This is why finding a reputable refiner is a key to making scrap gold buying business work. These people are the professionals and there are only a handful of them that are even worthwhile. The majority of those that advertise as a gold refinery, are simply middle men willing to send your gold to the real refiners. So when you find a good refiner, hold onto their number, because they are few and far between.