# de-ionized versus RO water



## Smitty (Dec 11, 2007)

Could a person use RO water to replace de-ionized water in the rinsing process. I've tested the RO (reverse osmosis) water for impurities and ph level. It seems safe to be used? Any suggestions out there? 

Salinity level = 0
Ph levels = neutral
Nitrates and Nitrites = 0
Chlorine = 0


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## Harold_V (Dec 11, 2007)

I have commented a number of times I used nothing more than tap water for refining (gold), and my quality was *outstanding*. The contaminants found in water do not report in gold once melted. There may be exceptions, one of them being water that is high in iron or manganese. You be the judge-----a picture of gold I refined is below. 

I consider the use of anything but tap water a waste of good resources. The average guy has such dirty work habits that he's inclined to contaminate his gold by many other means, assuming he has developed a process that raises the quality to the point of concern. I'm of the opinion that few achieve the level of industry standard, which is 9995. 

Harold


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## Never_Evil (Dec 11, 2007)

Harold, I dont care how many times you post that picture, I get all warm inside.

Smitty, Harold hits it on the head, water is pretty much water with the impurities being minimal.


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## Lou (Dec 11, 2007)

Nice picture, whether that be a 20 mL tiny evaporation dish, or (as I'm inclined to believe) a large dish, I'm sure liking the look of it. Hope you held onto it Harold, with prices these days. 


If you're going after anything above 99.99% 4N or 5N5 (puratronic and about 3X or more the spot price from Alfa) you'll be using some ridiculously expensive reagents and doing multiple precipitations in specially cleaned glass and plasticware.


Lou


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## Harold_V (Dec 11, 2007)

Lou said:


> Nice picture, whether that be a 20 mL tiny evaporation dish, or (as I'm inclined to believe) a large dish, I'm sure liking the look of it.


I should have placed something in the photo for a size perspective, but at the time, my purpose was simply to give a friend an indication of the color of properly refined gold. For the record, that is nothing more than a common household bowl, 6¼" diameter. The photo is dated a full 10 years after I closed the doors on my refining business. 

I'm a bit unusual in that I have a perfectionist tendency, so I was overly concerned about purity. I have never claimed 9999 quality, although one of my customers, when he (they, actually--two guys in a partnership) told me they had my gold assayed for purity and found that particular batch to run 9997. 

The level of quality I turned out required no pickle. Contaminations are almost always accompanied with oxidation on the gold surface, which often can be improved via pickling. The lack of need is an excellent indicator of quality, as is the surface finish on the gold. A frosted appearance is a sure sign of contamination. 

As I've commented previously, my practice was to refine a second time, all the gold that left my hands. There was never an occasion when improvement wasn't noticeable by doing so, witnessed by residues in solution after the second precipitation, although often quite sparse. Rarely did the remaining solution come colorless, although much discoloration was also rare. 

Water, the point of discussion, was always straight from the tap----the sole exception being the ice that was used in precipitation. The ice machine that was used is the type that forms clear ice, so it's obvious to me that impurities in the water were rejected as the ice formed. We still use this ice machine today----which was purchased for household use, not for refining. 

Tap water was used for all washes-----right down to the last one. It's obvious that minerals are left behind, but as I said, they do not report in the gold when its melted, although when one seeks superior quality, 9999 and beyond, I'm sure that would not be the case. Something would, indeed, report, enough to ruin the high numbers. Insignificant in the scheme of things for market quality. 



> Hope you held onto it Harold, with prices these days.


I'm not allowed to say!  



> If you're going after anything above 99.99% 4N or 5N5 (puratronic and about 3X or more the spot price from Alfa) you'll be using some ridiculously expensive reagents and doing multiple precipitations in specially cleaned glass and plasticware.Lou


Or perhaps even zonal refining. I fully agree-----once you cross the 9995 threshold, attention to every detail is a requirement. 

It makes little sense to worry about contaminations from water when dirty utensils are used-----or when solutions are not properly filtered. Good quality gold comes from paying attention to everything----including the cleanliness of melting utensils. As long as a person uses clean tap water, not water known to be of poor quality, I would make that my last concern if I was trying to improve quality of the end product. Only when attempting to achieve 9999 would I use anything but tap water, if even then. 

Harold


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## Lou (Dec 11, 2007)

A procedure I use for consistent 99.995% gold (though it usually is 5 9s) is for the digestion in quartz using ACS grade chemicals, then precipitation with Ultra High Purity SO2, I think the cylinder is from Matheson. That gold is redissolved in PTFE beakers using Spectra-grade acids (IIRC, I think it's ppb levels of 32 metals), boiled, concentrated, diluted with ~18.7MΩ UHP water, then precipitated with Mallinckrodt ACS trace metal oxalic acid. If further purity is required, the gold can be grown into crystals by decomposing the AuCl3 formed by taking that already pure gold and reacting it with electrolytically produced chlorine that has been treated to remove impurities. That gold is then melted in either quartz or glassy carbon, in vacuo or sold as the crystalline form in which it deposits. It's a bother to do but you can get some very nice crystals from it. 

EDIT: Should also mention that all of the glassware and utensils used are either tefzel/teflon or quartz and they all get a boiling in red fuming nitric, aqua regia, and nitric-perchloric mix. Also should say that zone refining is cool stuff, it's usually done with induction heating...I have a few zone refined pieces that I will have to find and take pictures of; if I can't find mine, I'll ask my friend if he's send me a few photos of his collection.

For 99.9% gold, I don't think tap water would make a hill of beans difference.

I've been meaning to show the difference between AuCl3 and HAuCl4* here on this board for a couple weeks. I see people use AuCl3 a lot and I occasionally get confused by it thinking they mean gold (III) chloride when they really mean HAuCl4, tetrachloroauric acid. I'm going to try and get these photos of my digital camera.

D'Oh edit again: those solutions below are really darn concentrated and are probably carrying a couple grams of gold each.


Lou


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## lazersteve (Dec 11, 2007)

Lou,

How do you get your hands on all this great equipment?

Do you buy the stuff or is your lab stocked by a company?

I would feel like a kid in a candy store with all the nice equipment you mention.  

Steve


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## Lou (Dec 11, 2007)

Long story really short, I work on alternative fuels.



Lou


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## Smitty (Dec 18, 2007)

Hey Harold, love that gold picture. Do you remember whether the shots were BB sized or larger? I'm still working on my first born.


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## Harold_V (Dec 18, 2007)

Smitty

Bear with me and I'll post a picture of some of the shot with an object that will help you grasp the size. It will likely be tomorrow night (Tuesday).

Harold


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## Irons (Dec 18, 2007)

I worked at a university that went from using distilled water to using Reverse Osmosis water. I asked about the differences and the reply was "cost". If produced with proper equipment, the RO water can be even better quality.


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## Harold_V (Dec 19, 2007)

A trip to the "big city" allowed me to retrieve some gold shot to take the photo posted below. Note that the coins are a US dime and one of the new bronze $1 pieces. 

Shot such as you see is prepared by pouring molten gold in a melting dish that has an aperture drilled through the bottom of approximately 1/8" in diameter. The molten gold fell to a deep stainless container that had a pump to keep the water in motion, preventing local heating. Size varies from about 3/16" flattened beads to miniscule round beads, but tends towards an average of roughly 5/32" in size. It was prepared in this fashion to serve the jewelry manufacturing industry. The small pieces made it easy for the benchman to weigh out a specific amount of gold when alloying, so it was by far preferred over ingot or button.

Harold


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## Smitty (Dec 19, 2007)

nice, it is about a BB size. There's more BB's there than I have for my rifle. Again thnx for the pics.


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