What's happening here?

[Barren Realms 007]

Steve's comments are right on target. I should have considered that, in his case, he primarily is dealing with recovered materials that are almost barren of base metals. In such a case, a short wash may be (and probably is) adequate. Key to success is the one single indicator that displays the intended results----further washing does not yield a discolored wash solution.

Harold

I will find out when i wash it in some HCL the see if it cleans up. But it is such a fine powder there might not be much contamination just looksreal black because it is so fine and not coagulated. It has settled now and i need to decant the solution. The solution is a darkish green color (olive green). I'll see if Ican find time to finish the batch this weekend and run the percipitated gold thru process again.

 

[Harold_V]

For the record, it was my experience that the darker gold precipitated, the more it was contaminated. When it's fine, as you described, it's entirely possible that contamination is locked in in such a fashion that it won't wash out. That's the point of re-refining.

For years, my process of precipitation (by choice) was to use SO2 from a cylinder. It has huge benefits in that you don't increase volumes, which, to me, was very important, but the best benefit was not adding any substances that had the least bit of a chance of changing the color of my solutions. As a result, when I precipitated my gold, it was absolutely clear to me if it would be relatively pure, or not. When the solution was heavily contaminated, such as when precipitating from filings, which I mentioned earlier, the quality was never acceptable. It was, in fact, so bad, that it was that gold that was melted and used as my added gold when evaporating. That way, it received two more opportunities to be purified.

One other thing I'd like to mention. For many years, I routinely re-refined my gold. It was one of the things that set me apart from my competition, and insured that I never received complaints of casting problems, or brittle gold. What I learned from that experience is that when gold is precipitated from relatively highly concentrated solutions, it comes down what I like to call blonde gold. Instead of the dark bronze color with which most are familiar, it came down a very light cinnamon color----and on rare occasion, as fine (shiny) crystals. Such gold, when washed, gave up no color. It was relatively safe to assume that it was better than 9995 when it was dissolved, but there is no guarantee that is the case, so everything got re-refined.

It was common to find a hint of blue in my solutions after a second refining. Proof positive that even the best washing procedures do not remove all contamination.

In order for me to have improved my quality beyond that which I delivered, it would have likely required not using tap water in the process, and maybe even switching to reagent chemicals instead of tech grade. Considering my gold could be melted without flux, and without oxidation, it was clear, at least to me, that my processing was beyond reproach. I exceeded the industry standard on a routine basis, and was content to pursue refining in the manner I chose. Damned few people here will ever be content, always looking for something better.

It's easy to find. It's all in Hoke, where you, too, can learn to process gold of this quality:


Harold

 

[Barren Realms 007]

One other thing I'd like to mention. For many years, I routinely re-refined my gold. It was one of the things that set me apart from my competition, and insured that I never received complaints of casting problems, or brittle gold. What I learned from that experience is that when gold is precipitated from relatively highly concentrated solutions, it comes down what I like to call blonde gold. Instead of the dark bronze color with which most are familiar, it came down a very light cinnamon color----and on rare occasion, as fine (shiny) crystals. Such gold, when washed, gave up no color. It was relatively safe to assume that it was better than 9995 when it was dissolved, but there is no guarantee that is the case, so everything got re-refined.

Harold

Thanks Harold I'm sure you have mentioned this before. High concentrations. What would you consider as high.

Johnny this answers your question about your avatar picture.

 

[Harold_V]

Thanks Harold I'm sure you have mentioned this before. High concentrations. What would you consider as high.

Contrary to the opinion of some on this board, heat is the problem with concentration. Clearly, you have great difficulty precipitating five ounces from a liter of solution.

My target, when re-refining, was to have about 18 troy ounces per liter of gold chloride. To that, I added three liters of ice prior to precipitation, which was a requirement, not a luxury. Without the ice, the solution reached a temperature whereby the gold ceased to precipitate. Even with ice added, it was common for my barren solution to be so hot that some gold refused to come down. The addition of a little more ice would instantly drop the gold, however.

So then, if you have three ounces or less per liter, you may have success without the addition of cooling. That is one of the advantages of working with dilute solutions. I preferred not to.

Harold

 

[Lou]

Harold,

The reason why the gold would refuse to come down is that the solution was so hot and so saturated with ions it would not hold any sulfur dioxide--this means that all of your gas quickly left the solution. As you know well, the solubility of a gas in a liquid decreases with increasing temperature. Sulfur dioxide is no exception.


I should emphasize to everyone that the cooler you keep your solution when precipitating gold (keep it below room temperature), the happier you will be.

 

[Barren Realms 007]

:!:

 

[Harold_V]

Harold,

The reason why the gold would refuse to come down is that the solution was so hot and so saturated with ions it would not hold any sulfur dioxide--this means that all of your gas quickly left the solution. As you know well, the solubility of a gas in a liquid decreases with increasing temperature. Sulfur dioxide is no exception.

That's an interesting observation, but I question if it is theory, or fact. Here's why. The instant ice was added, there was an immediate cloud of gold formed. It's as if the reaction is exothermic, and had to lose heat in order for the reaction (precipitation) to take place. You should also note that the solution had an overwhelming smell of SO2, so it was apparent to me that there was enough present.

None of this is intended to be a challenge to your comments, Lou. I'm simply hoping to get a firm understanding of something that perplexed me for years.

Harold

 

[Barren Realms 007]

Harold,

The reason why the gold would refuse to come down is that the solution was so hot and so saturated with ions it would not hold any sulfur dioxide--this means that all of your gas quickly left the solution. As you know well, the solubility of a gas in a liquid decreases with increasing temperature. Sulfur dioxide is no exception.

That's an interesting observation, but I question if it is theory, or fact. Here's why. The instant ice was added, there was an immediate cloud of gold formed. It's as if the reaction is exothermic, and had to lose heat in order for the reaction (precipitation) to take place. You should also note that the solution had an overwhelming smell of SO2, so it was apparent to me that there was enough present.

None of this is intended to be a challenge to your comments, Lou. I'm simply hoping to get a firm understanding of something that perplexed me for years.

Harold

Would this do the same thing at around 75-80F when you add a very saturaded amount of SMB and you do get and excess of SO2 bubbles on the top of your solution?

I didn't test with a thermometer to see if there was an increase in temp., and didn't really notice any change from feeling of the container.

Would there be a possability of sdding a small amount of SMB again but with the temp of the fluid droped to around 45-50F to see if any thing percipitates?

 

[Harold_V]

Would this do the same thing at around 75-80F when you add a very saturaded amount of SMB and you do get and excess of SO2 bubbles on the top of your solution?

It's not clear to me if your question is addressed to me, or Lou.

My experiences, all of which were identical, was that there was never a problem with precipitating the last traces of gold unless the solution was exceedingly hot. It would be uncomfortable to handle, well above 110°F. Because I precipitated large volumes when re-refining, this was an ongoing phenomenon. It was consistent, the only variations being the amount of gold per cylinder. When it was low enough, there was not a problem with precipitation because the temperature was low enough.

Keep in mind, I started with four liters of fluid, three liters of which was just ice. The amount of heat dissipated in precipitation is quite high. I expect that all of the energy that was absorbed in dissolving the gold is now returned.

I didn't test with a thermometer to see if there was an increase in temp., and didn't really notice any change from feeling of the container.

If you have a practice of diluting your solutions with three volumes of water, plus you add water with your precipitant, it is highly doubtful you would notice much temperature change. Remember, I'm talking about 18 ounces or more, in four liters.

Would there be a possability of sdding a small amount of SMB again but with the temp of the fluid droped to around 45-50F to see if any thing percipitates?

None of this is magic. If your solution tests barren, unless there is unprecipitated gold chloride locked in that which has already been precipitated, there is no reason to expect any further precipitation. That might not be true if your solution was over heated, however.

The unprecipitated gold chloride I speak of is a very real phenomenon. Because of the huge volume of gold particles that come down from concentrated solutions, just like contamination gets dragged down, so, too, does gold chloride. When all of the gold was down, it was required of me to stir the resulting gold to liberate the balance of gold chloride. Solution that tested barren prior to heavy stirring suddenly tested positive for gold. Depending on circumstances, it wasn't unusual for me to have to stir more than once, continuing with the addition of SO2.

Harold

 

[Barren Realms 007]

I started taking the cover off of these and thought I would share some pictures.











http://www.youtube.com/watch?v=mIUxgH6u4DE

If the forum would like the other individual pictures of the item's posted let me know and I will be glad to post them.

 

[goldsilverpro]

I love all that stuff, especially that in the left half. All-gold side-braze packages run high - lots of gold braze. The little 14 and 16 lead ones can run $300/# - $400/#. Great stuff! The TO3s in the bottom pic aren't worth much at all.

 

[Barren Realms 007]

Yea I figured that would be worth posting a pick on.

That stuff has gold all in it. I'm going to have to go into the ceramic's on these to get it all. 8)

Would a cell be ok for those TO3's? I am not sure if there is plating on the inside of them I haven't seen it mentioned.

 

[goldsilverpro]

Would a cell be ok for those TO3's? I am not sure if there is plating on the inside of them I haven't seen it mentioned.

I doubt it. Pop one open and see what's there. Some have zero gold. The best ones (old) are completely gold plated but are often covered with black paint. The TO3s are made in at least 6 or 8 different ways. The ones you have look to be one of the worst type. If you can't see gold somewhere on the outside, they're usually not good.

 

[Barren Realms 007]

Is this what you are talking about?

 

[Barren Realms 007]

The little 14 and 16 lead ones can run $300/# - $400/#. Great stuff! .

Would the small ones have more of a yield then the large ones above them?

And for them to get that amount I would guess the yield to possibly be .6-.8 oz per lb for a yield.

If you were to some how put them in a cell would it deplate the gold from under the ceramics?

But I really like these myself.

 

[goldsilverpro]

Would the small ones have more of a yield then the large ones above them?

Per pound of parts, yes - not per unit. The bigger ones have a lot more ceramic but about the same chip area and lid ring area (those are the areas where the gold braze is, which makes up most of the gold value). Therefore, the small ones are worth more per pound.

And for them to get that amount I would guess the yield to possibly be .6-.8 oz per lb for a yield.

$300 - $400/# = .26 - .35 oz/#

If you were to some how put them in a cell would it deplate the gold from under the ceramics?

No. The sulfuric cell essentially won't attack the Au/Sn braze under the lid or the Au/Si braze under the chip. Those materials might take days to strip, if they strip at all. It generally works well only on gold plating.

 

[Barren Realms 007]

And for them to get that amount I would guess the yield to possibly be .6-.8 oz per lb for a yield.

$300 - $400/# = .26 - .35 oz/#

How are you going to make a profit paying spot gold price? 8)

 

[goldsilverpro]

When I say value or worth, I mean intrinsic gold content.

 

[Barren Realms 007]

When I say value or worth, I mean intrinsic gold content.

I was figureing you ment that after I wrote the reply, sorry. It was the way the first post was implied I thought you were implying scrap value not gold value. Sorry for that.

 

[Barren Realms 007]

I got a small problem here. This is the drop I had after I added SMB.

The make up of this group was silicone chips from pentium pros, possibly tungeston from pp's, high grade ceramic chips, some fingers after processe, some pins after processed.

This stuff was washed in HCL,water washes till no more color changes before I disolved the material in HCL/Clorox. There was nothing odd about the group before I disolved it.

After I disolved the material I added 1/3 volume of water and evaporated to remove the chlorine. It was then doubled in volume with water and container put in ice bath and solution filtered thru a charmin plug. The soution was then evaporated to remove water. It was then put on an ice bath for a little bit and then SMB was added. The solution was a nice brownish red with no sighn of any contamination before the SMB was added.