Dan is OK. He can be a friendly and all. But honestly in the end, it would be better to look it up in a book. At the end of the day, all those high priced consultants can be pretty stand offish. You would think they were the only ones who knew how o breath air.
Stainless steel wool charges are a special case. Depending on your mix, do a variation of this.
100 grams charge
Borax 30 grams
Silica 125 grams
Sodium Nitrate 150 grams.
For a sulfide ore charge
100 grams charge
Borax 40 gms
Silica 40 gms
Nitre 20 gms
MnO2 30 gms
Na2Co3 25 gms
But for those tough or low grade cases:
Lead will get your flux into a low temp thingie, which allows easy pouring, but given that it is an efficient collector of gold, you will need manganese dioxide (MnO2), borax, silica, perhaps sulfur, fluorite, and baking soda, or sodium hydroxide. Fluorite CaF2, will help with clays and make your charge more fluid. Silicate slags tend to be viscous. Hence the borax, manganese and fluorite.
The Tavener Process (Lead as red lead or litharge)
Do it like this. Take all your charge and figure the silica. Do a make up where you add enough silica to bring the silica content to the same weight as your original flux. The take your carbonate and metal oxides and figure the amount they stoichiometrically combine with the silica in a one carb metal oxide or basic oxygen to one silicate oxygen. Na2Co3 become Na20 so it's 2 Na2C03 to one SIO2. FeS2 becomes Fe0 so it's 2 FeS2 to one SIO2. (You will need an oxidizer, KNO3 or NaNO3 Red Lead is Pb so, 2 PbO to 1 SiO2. And so one until you have used up all your natural carbonates and against your charge of silica in this one to one ratio of oxygens. Then you split the "unsatisified silica" with the stoichiometric satisfaction of added Pb (as Pb0) and "equal parts" Na2Co3 or NaoH. In other words do half the silica with lead and half with sodium carbonate. Do that until all your silica, added and natural in the charge, becomes oxygen balanced with natural and added metal oxide and carbonate. Always work with the weight of the original material in weighing out, not the GMW of the oxide. So Na2C03 is not Na2O, but the Na2O gives the ratio. The weight is as Na2C03 which is 130 grams GMW not 86 gms. And Borax BTW is Na2B4O7, but its stoichiometry is One basic oxygen to 6 acid, so it is oxygen equivalent in a monosilicate ratio to 3 SiO2. So its 1 Na2B4O7: 3 SiO2.
Then take the silica and "replace" 10 to 15% of it with Borax. The ratio of replacement will be 5 gms borax to 3.57 grams silica. Add some more borax, about 5% of the charge weight to the top of the charge and put it in a hot furnace, bringing it back to bright yellow heat. (1.5 hours or thereabouts) (1857 to 1940 degrees fahrenheit by optical pyrometer or ceramic cone.) Remain there for 5 minutes and pour the lead button into an iron cone. You can also pour into a ceramic crucible Let cool completely. Then break off the lead button, square it up, and put it on a bone ash or mangnesium dioxide "dish" or cupel. Drive the lead with a slightly opened furnace or added air at 1600 degrees fahrenheit until the lead is absorbed into the cupel and a bright silver or gold bead is visible. Wait until the bead winks at your and then let it sit for a few minutes, then take it out. You can also take the lead into acid, making lead nitrate. This has its problems too, but avoid hot lead fumes to a degree. Of course you get nitrates evolviong from your fume hood and with volumes of extraction involved it is a bit more than a lab experiment.
Cuppelation of lead produces lead fumes which you must collect in a baghouse and/or in a bath of lime water, but if you have the equipment it is one of the more efficient gold collectors. Always, always test your slag and reuse it. Some gold slags can run 1200 ounces to the ton after first pour. After they are down around 10 to 50 ounces to the ton after 5 to 8 resuses, they can be discarded. The percentage is low in the scheme of things. They can also be reground and cyanided.
If you have lots of steel, then you need to oxidize it to FeO agsinst the silica. Add about 10% NaNO3 of the weight of silica to oxidize a heavy charge of metals. Remember to calculate the weight of Ni and Fe so they can be silica satisfied in Ballings calculation. If you have a lot of black sands estimate the iron as Fe2O3 and Fe3O4 as 3 FeO. You may need carbon if there is a lot of oxide in the charge. You don't need much. 11.7 grams of carbon (flour or charcoal) will satisfy or reduce 453 grams of black sand. 2 Fe3O4:1C. You don't want to add too much if in fact your charge has reducing properties otherwise you will bring down an iron button which will collect gold! No problem to clean that with nitre and a new charge however.
The amount of Ti02 needs figuring too. A lot of black sands are titanium (ilmenite). Iron sands have excess oxygen. Sometimes sulfur is added to such a flux to generate SO2 and reduce the iron a bit. Normally in black sands there is enough yaller pyrite to do the job and you may not need the carbon. you may need trial to figure out the reducing/oxidizing power of the charge. This can be done against lead as reagant and the amount of lead brought down will tell you the RP of the charge.
It sounds like your golden BB's were a too low silicate charge and it needed too high heat. So you were too cold. Borax will bring that necessary heat down. It probably poured in lumps. If the melt is right the metal will flash by when the pour is at about 30 degrees down, before all the rest of the melt. You could stop there and just collect the gold half the time.
The green glass was the nickel slag.
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