kurtak
Well-known member
Could be any of those things & as well it could be silver chloride &/or combination of any/all those things
Kurt
Gold filled batch, strange white stuff after drop?
- Thread starter Hartbar
- Start date
Help Support Gold Refining Forum:
Kurt
cejohnsonsr1
Well-known member
- Joined
- Sep 20, 2020
- Messages
- 260
The gold on fingers and other similar scrap is plated over the copper. The gold used to plate is pure. i.e. 24k. It is not an alloy.
cejohnsonsr1
Well-known member
- Joined
- Sep 20, 2020
- Messages
- 260
Gold filled is, indeed, different from gold foils. The foils that remain after parting the underlying metals, however, is pure gold. It’s not an alloy. Gold filled is a very heavily plated scrap. Plated is never an alloy.
Gold filled is an alloy. That is why it is 1/10 12k or 1/20 14k for example. It is not plated but layered together. There used to be a video on YouTube that showed and explained the process very well but I haven’t seen it in a while. The base layer is laid out and an alloy of the needed karat gold is layered on top of the base metal. Then placed onto whatever base is needed to form the intended piece, usually in the form of jewelry. When we process it we use (typically) nitric acid to dissolve the base material out from under the layer of karat gold. This usually leaves the heavy gold foil and some amount of the base metals that tend to migrate into the karat gold. This is why the foils lean to the “dirty” side versus true karat gold. The base metal can vary widely causing more problems in the refining steps than karat gold as well since every piece in a lot can potentially be a different mixture. With the base metal gone it then become a dirty form of karat gold.
That is not correct. From Wikipedia: you have a hollow sheath that is filled with another material.
Often jewellers brass but not always. any kind of cheap material will do but gold coloured is preferred as the colour will not shine through if the gold get thin during rolling or other processing.
Shark beat me to it again
I don’t mind being checked up on as I may be wrong. It is nice to have competent people watching out for us.That is not correct. From Wikipedia: you have a hollow sheath that is filled with another material.
Often jewellers brass but not always. any kind of cheap material will do but gold coloured is preferred as the colour will not shine through if the gold get thin during rolling or other processing.
Shark beat me to it again
As a side note… when looking at older gold filled chains you can see the color change in the form of a darker colored gold, often looking more copper than gold. This can happen because the small chains are limited by their size. No room or to little room is left to add an adequate barrier layer allowing the base metals to migrate faster and or deeper into the gold. The larger the piece the better the gold color seems to hold up.
If you see, my reply was directed at cejohnsonsr1, not you. I just filled in a bit extra since you beat me to the reply
- Joined
- May 6, 2021
- Messages
- 116
I believe this is factually wrong. The foils left after a couple of nitric leaches on gold filled, are not pure.
I rinse thoroughly and incinerate well, then weigh pre AR. I get less than 50% pure powder weight after completion. That’s because 10k (41%) pure, and 14k (58%) is my source material.
It has been explained by Shark higher up
https://goldrefiningforum.com/threa...ange-white-stuff-after-drop.31474/post-332329
cejohnsonsr1
Well-known member
- Joined
- Sep 20, 2020
- Messages
- 260
I stand corrected in the sense that gold filled can indeed be karat gold on the plated sheath. However, from a practical standpoint, the non gold components of the karat gold and the filler metals turn out to be pretty close to what you’d get if you inquarted regular karat scrap. The resulting foils after parting with distilled water and Nitric acid is effectively pure gold around 99 fine (if done properly and pure being used in the relative context). A 2nd refining and precipitation is required to get to 999 fine, as in any other process. I hope that clarifies what I was trying to say the 1st time around.
Joecast
New member
I am trying to refine gold filled jewelery. Sodium nitrate hydrochloric acid . has worked some what but I am following instructions for electronics scrap. I’m trying to do this with out nitric acid. I have had some success sulfuric acid what is the 12 V battery charger . I am wondering if you or someone can you give me the right direction with the recipe designed for gold filled jewelry. Thanks
The crude basics are to place the gold filled in container large enough to have plenty of room. Add nitric and an equal amount of waterto it and heat it watching out that is does not boil over. Do this until the base metals are gone, notice the material will start moving around as they get lighter. Once they stop reacting to fresh nitric. Remove the foils and process them in AR.
If trying to avoid nitric acid you can use hydrochloric acid. Place half gallon of hydrochloric acid in 5 gallon bucket, add half gallon of water. Add gold filled, not more than one pound. Add 1/2 ounce of 3% peroxide. This will take up to a month as is. Adding a fish aquarium air pump will speed it up some, but is still slow. This also will leave more waste acids to clean up.
A little busy right now, will be able to better explain later this evening.
Last edited:
Yes. For me, it jumped out of the text also.
Maybe it would be better to correct it in Sharks post and leave a notice.
Maybe it would be better to correct it in Sharks post and leave a notice.
The battery charger is just that. A manual battery charger for a car. It has to be the manual type as the newer electronic/digital will kick off since it will not “see” the proper connection. It is used as a power source for a sulfuric cell, also known as a gold stripping cell. Used mainly for gold plated items, it can work for gold filled just slower which can pose other problems. Over heating the cell can be one of the big problems.
Trying to refine gold without nitric acid is pretty tough to do. If we use a nitrate salt to process gold we are still using nitric acid. In the process the nitrate is converted to nitric. The main difference is the nitrate salts need heat to produce the nitric. Real nitric acid will work at room temperature but starts off a bit slower. It is one of the other trade offs to reach a specific goal.
Using work around methods present opportunities for more problems. This often is the reason they aren’t recommended or discussed much. It is normal when using these methods to take longer, generate more waste, or need more chemicals to achieve near the same results. What they can do is allow some to make a pretty piece of gold from some materials that they may not be able to otherwise.
The method used by the original poster can best be explained in the video he posted from Geo. It is also where I learned to do it from.
