Large Black gold nugget found -- do I clean it?

AU79 Prospector

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Hello everyone! First post here but long time reader :)

I recently found the biggest gold nugget of my life highbanking -- Weighing in around 6 grams. What's unusual about it is that.... it's coated with something black (manganese oxide I am guessing). My claim is in Virginia near an old hard rock mining operation.

I used soap and a toothbrush to bring out more of the gold color... but now I'm not sure what to do with it... do I clean it more? Put it in a rock tumbler? Muriatic acid? Or leave it Au natural? Would love to hear your thoughts.
 

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Hoser John

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Simple bleach will clean the oxides off ,and not tarnish it, but it really looks more like a pt. group metal to me for some reason. If so at 6 gram+- worth a pretty penny either way-John
 

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AU79 Prospector

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Simple bleach will clean the oxides off ,and not tarnish it, but it really looks more like a pt. group metal to me for some reason. If so at 6 gram+- worth a pretty penny either way-John

It's not a very good picture because I took that right before A thunderstorm so it was really dark. I am uploading a picture taken in the sunlight and it looks much more like a Gold nugget then. Thank you for the suggestion!!
 

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IdahoGoldGettR

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The use of soap and a toothbrush seems to have done a remarkable job of taking some of the tarnish off. I have had many pieces of gold with the same manganese oxide "stain" and saw some good results cleaning them with a diluted nitric acid solution. I typically start off with a 50/50 mix of nitric acid and water, leaving the gold sit in this solution for several days or better. During such time , I do shake it once in a while (just because i can't help myself but think it helps speed up the process. Lol). It's not uncommon for me to make this solution slightly stronger but I have never pushed the envelope than using more than 2/3rds acid and 1/3rd water. Any stronger and I believe there will be risks of the acid eating away at the gold. Patience is the key here and so I suggest beginning with the weaker solution and let it work for you. Just my 2 cents on the subject . Nice nugget by the way. Cheers to you. :icon_thumleft:
 

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Aufisher

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Nice nugget! I would leave it black and then play with it every day until it glows!
 

Assembler

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Hello
Nice nugget and thanks for posting.
 

huntsman53

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Congrats on a nice Gold Nugget! If you ever plan on selling it in it's Nugget form, it would be best to remove the blackening from it. I say this, because it might be a hard sell with the black on it with potential Buyers questioning whether it truly is Gold.


Frank
 

Jordun

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Just the eyes .....I don't think they would trust me with something as technical as a detector
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I'd leave it black and drop that sucker in a fishtail for safe keeping ......."no one ever checks the fish tank"
 

johnedoe

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I would leave it as is.... It is worth more to a collector that way and a collector will know what he is buying.
 

trdking

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I would leave it as is.... It is worth more to a collector that way and a collector will know what he is buying.
John D Is absolutely correct. Do not clean it. It is worth more than 3x the gold weight as a collector specimen and they want it Aunatral
 

trdking

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You found a one ounce nugget and you are still drinking Pabst Blue Ribbon?
Yes Sir! Only the finest for me!

I inherited this nugget from my Dad. He found it scuba Diving/ Prospecting the middle fork of the feather river in 1958. Started a gold fever that almost divorced him from my mom :) Can you blame him?
 

mytimetoshine

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banner?

Sent from my SAMSUNG-SM-G920A using Tapatalk
 

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AU79 Prospector

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Thank you guys so much for your expert advice! I am going to first try and put it my rock tumbler with stainless steel shot first and then re-evaluate. I will post a video when done =)
 

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et1955

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Have you thought of taking it to jeweler for cleaning or at least ask for advice on cleaning it, tumbling with ball bearings might damage it since gold is so soft.
 

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AU79 Prospector

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Have you thought of taking it to jeweler for cleaning or at least ask for advice on cleaning it, tumbling with ball bearings might damage it since gold is so soft.

I've done a lot of research on this -- apparently one of the best ways to clean jewelry that does not have stones in it is actually using a tumbler with small stainless steel shot is to burnish the gold. I tested this out on my wedding band and it looks AMAZING -- nearly brand new!. Because the stainless steel shot is bigger than the crevices in the nugget , it won't burnish that part so it should remain black to give it a cool 3D look. The chemical methods will get rid of all the black -- it would be clean but with no personality as people above have pointed out. I'll post the outcome when done.
 

arizau

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I've done a lot of research on this -- apparently one of the best ways to clean jewelry that does not have stones in it is actually using a tumbler with small stainless steel shot is to burnish the gold. I tested this out on my wedding band and it looks AMAZING -- nearly brand new!. Because the stainless steel shot is bigger than the crevices in the nugget , it won't burnish that part so it should remain black to give it a cool 3D look. The chemical methods will get rid of all the black -- it would be clean but with no personality as people above have pointed out. I'll post the outcome when done.

While your method seems to meet your satisfaction, a gentler way that is sure to preserve character and some of the coating is to tumble it in crushed pecan shells. That method is commonly used and the media is available online, maybe a local rock shop, or a store that sells reloading supplies. There may be a local pecan shelling plant in your area too(?) and you can make your own from a couple of pounds of them.

https://www.google.com/search?q=pec...chrome&ie=UTF-8#q=pecan+shell+polishing+media
 

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