Non-Chemical melting my button

[Anonymous]

I just received my Hokes in the mail and can see that this is going to be some tough reading. It seems more a compilation of techniques rather than a step 1 step 2 method. OK everyone says treat there scrap with Nitric Acid first to remove those pessky metals, where can I get it? I am in central florida and I see that eBay has taken it off their site. Google is of little value and I would like to do this right. Should I condense my own with distillation tubes etc from the aqua regia like Steve says on his CD, if so that should take quite a while, if not I sure would appreciate some help. Do most of you hunt and peck through hokes or start at page 1. Their appears to be a lot of older terminology that I would love to find translations for. Is this a fools errand for a person with little chemistry background since I see different camps concerning methods here already and I unfortunately jumped on the Shor bandwagon (knowing little else) and would love to find the right way. I will let you know what I have gleaned from Hoke as I waddle through. Thanks for everything so far. Frank. BTW I bought a small graphite crucible, can I heat it from the outside with MAPP gas and expect to melt gold or should I go to Oxy-MAPP and apply directly to the gold?

 

[lazersteve]

Should I condense my own with distillation tubes etc from the aqua regia like Steve says on his CD, if so that should take quite a while,

Frank,

I must step in an correct you here, no where on my DVDs or on the forum do I recommend distillation of nitirc acid for use in refining.

The nitirc acid recipie I have provided is a cold method that requires zero distillation and the requires only about 45 minutes to an hour to complete.

I have a feeling you are confusing me with someone else. I have not published a DVD to date showing me using aqua regia. You also mentioned a CD instead of DVD.

Can you tell me the title and author of the CD you are referencing?

Thanks,

Steve

 

[Noxx]

Maybe he's talking about the other Steve (Noble Metals, LLC)
He showing how to refine gold using Aqua Regia but he doesn't show how to distill nitric acid...

 

[Anonymous]

I was referring to the Noble Metals DVD (sic) and looking at it again he is talking about a cold condensing method of recovering nitric acid from the gas from AR working on CPUs. Anyway I have spent the last couple of hours going thru your download - 126 pages and marking it up with a highliter so that it looks like s kids coloring book and I am finding many items that cross reference back to Hokes (which I just received today) and many, many methods, so I think I am now generally confused enough to get started. One general question though, AR OR NOT AR - that is the question, wether it is nobler to start with Nitric Acid or Not --- I digress, give me some time to absorb this sensory overload of information and I will begin the new questions. BTW anyone have an answer about the graphite crucible or should I just get some cupels??? Thanks again. Frank

 

[lazersteve]

I bought a small graphite crucible, can I heat it from the outside with MAPP gas and expect to melt gold or should I go to Oxy-MAPP and apply directly to the gold?

Frank,

Graphite absorbs heat like there is no tomorrow. With some work plain old MAPP gas can be used to get the gold molten in a separate dish and then poured into a hot graphite mold successfully.

Since your question specifically states a graphite crucible, I would have to say you won't have much luck melting the gold directly in the graphite cruible unless you are supplying the MAPP via a gas furnace configuration as opposed to via torch. Even with oxygen the torch most likely won't cut the mustard. In short, it's hard to get gold up to it's melting point with a MAPP or MAPP/OXY torch when it's in graphite.

Steve

 

[Noxx]

I totally agree. I never succeeded either.

 

[Harold_V]

I'm at a loss to understand why you're asking about cupels. They are intended for cupellation, not melting, although cupellation revolves around molten metal. Cupels are likely to have but one use cycle, unlike a properly seasoned and fluxed melting dish.

I suggest you find a jewelry supply house in your area and buy small clay melting dishes for your purpose. They come in sizes, so you can buy one that fits your needs. They're not expensive, and have a good life span, assuming you handle them properly at the outset. If you are not familiar with proper procedure, ask and I (or others) will give you a blow by blow process to insure a useful life.

You are wise to avoid using graphite. It's not cost effective, and, as Steve suggested, it's a wonderful heat sink.

Harold

 

[Anonymous]

Thanks for all the feedback, I am now looking for the clay melting dishes. Let me ask, when they are properly prepared, will MAPP gas provide sufficient heat for melting or should I go to a MECO micro torch etc and use MAPP-Oxy or any other suggestions. Thanks again, Frank.

 

[goldsilverpro]

I totally agree with Harold. Jeweler's Melting Dishes are the absolute best way to go for torch melts. There are 2 types: the less expensive round sided type and the heavier ones with flat sides. The heavier one looks almost exactly like a big cupel. I would suggest using the heavier one and buy (cheap) the handle for it, also. There are 2 types of the heavier ones - get the flat type without the shield - about an inch thick by about 3" wide. I once saw a jeweler get 25 oz of pure gold in one of these dishes. I only do 10 ozs at a time. I like to use a small rat-tail file to form a shallow spout on the edge of the dish. I would buy at least one extra dish. Use one for very pure gold and the other for things like karat gold. If you're doing silver, get another one. I like another one for inquarting. And then there's platinum. The less cross-contamination, the better off you'll be. The dishes aren't cheap, but, with care, they'll last for many, many melts. I don't worry much about BB's left in the dishes. I'll get them next time.

If you insist on using cupels, don't use bone ash. They have a tendency to fall apart. Try the cheaper Composite cupels, with Portland cement in them, or the Marbor type. However, some of the cupel will likely be stuck to the bottom of the button. I only use cupels in a pinch.

A better substitute for a melting dish, than a cupel, is a standard clay assay crucible, which many of you have, I think. I've seen them sold on Ebay as melting crucibles. I use the 30 gram size - maybe, $1.50 to $2 each - maybe more. On the inside, they have a rounded bottom and work well as melting dishes. Lay the crucible on it's side on a hard surface and carefully break off the top section of the crucible with a hammer. You can nibble them down with the hammer, or you may find that pliers work well. End up with the crucible about 1-1/2" to 2" tall - jagged edges are OK. Treat it as you would a melting dish. If you want to reuse it, pour the metal into a mold or into shot, instead of letting the button freeze in the crucible. It's hard to get the buttons out without screwing up the crucible.

 

[Anonymous]

If interested I found a jewelers web site www.contenti.com and they have the melting dishes as well as many other supplies. This is quite a learning experience but I am finding it quite stimulating and my wife says that she hopes it will keep me out of trouble. Thanks to everyone again. Frank.

 

[lazersteve]

Frank,

I sell melting dishes on my website.

http://www.goldrecovery.us .

Steve