99.95% gold vs 99.99% gold

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lazersteve

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While I was doing some mental exercises today I came up with some interesting information about the difference between 99.95% gold and 99.99% gold after doing some basic math.

I wanted to know what the difference really is compared to some common items that may contaminate gold.

Here's what I came up with:

These numbers will be based on a single troy ounce of gold. The weight of the troy ounce gold will be considered as 31.1 gms for sake of this example:

We have 99.99% - 99.95% = 0.04% difference in purity

0.04% x 31.1gm / 100% = 0.01244 gms difference in weight between purities.

To put this in perspective here's what I've found:

A grain of sand 1 mm x 1 mm x 1mm (1 cubic mm) weighs 0.0026gm
A cubic mm of water weighs 0.001 gms
A cubic mm of air weighs 0.00129 gms

With these basic weights we can determine that a troy ounce of 99.99% gold degrades to 99.95% if it :

Had 0.012 cubic centimeters (mL) of condensation on it !

OR

Had 5 grains of sand stuck to it !

OR

Had an air pocket only 0.0096 cubic centimeters (2.13 mm x 2.13 mm x 2.13 mm) in it !

So the troy ounce of 'ultra pure' gold of 99.99% is guaranteed to have no sand in or on it, no condensation on it, and no air pockets in it when weighed!

This doesn't even take into account the affect on the scales due to air currents, oils from the fingers, or stray metal bits that may hitchhike on the gold bar when weighing. These 'ultra pure' bars must be weighed in totally dry, 100% clean rooms, handled with lint free gloves on, and weighed in a covered scale when they are created.

I don't think I'll ever produce any 99.99% pure gold at home. It's something to think about when discussing gold purity.

Steve
 
:wink:

As far as I'm concerned, I'm happy with 22K as a final product for now. It sells well and .999 or even .995 costs way too much in "acid fees" to refine at that level.

If I can get 22k guaranteed with my testing solution I'll be happy at this point.

For those that are following my trials and tribulations, I just filled my cell again, but I diluted it this time (thanks for the mini-tutorial goldsilverpro!) according to my calculations I have 68% sulfuric.

The 94% seemed way too thick for me at this point. Maybe when I'm more experienced and I have better quality materials... ect.

Don't get me wrong, the 94% worked wonders on what I did, but I like to see what's going on in the cell and an hour into it, the 94% looked like motor oil.

So now, after dilution, I think the cell is cooled down enough so no more typing.... I have more important things to do now. 8)

keep it up guys, I've been home to a few hours and I can't even make it through all the new posts!!

that's a good thing
 
If you're using aqua regia, it's as easy and as cheap to get 999.5.

I don't think I ever said 68%. Is that by weight or by volume? Keep us posted on what happens.
 
Interesting numbers, Steve, but there are some things that may not be too apparent to you. For one, the likelihood that you'd find air pockets in pure gold are not good. That condition tends to come from within-----but you don't have that problem unless the gold is contaminated----at which time blame shifts to oxides of the contaminant. You can even use plain old tap water and achieve a level of purity beyond 9995------I did it routinely.

I used an analytical balance when weighing and marking ingots. It was capable of reading the weight of a pencil line, so the level of sensitivity was quite good.

It's not as hard to weigh these things as it might appear, but you were right in suggesting that they must be used without drafts. The balance in question is contained within a glass enclosure, so you can, and do, weigh in still air. My ingots were boiled in sulfuric acid and water before being weighed, and were handled with cotton gloves. Once weighed the gloves were no longer used, but you had to handle the ingots with care because they get surface scratches even from your skin, assuming the gold is high enough in purity.

If gold forms tiny crystals on the surface when it cools, that's a good sign the gold is not pure. Should you melt a button of pure gold in a dish that is treated with enough borax to lubricate the dish, the button, say, two ounces, if allowed to cool naturally, would have a very shiny surface. broken up by a few crystal lines. Each crystal tends to be a good portion oof of the button, which may be broken up into a half dozen zones. The button would pull a significant pipe as the center froze----the larger the better. None of these features should be construed as an assay, but anything less is a sure sign that your gold is not pure.

I'm not trying to promote your agenda------and I see nothing wrong with the level of quality you're creating, nor that of anyone else, not as long as it meets your criterion, which you've made abundantly clear. You refine for pleasure, and it's not a business. My only point in shooting for industry standard (9995) is that your gold becomes useable to people that are willing to pay spot price. As long as you're happy with what you're doing, it really makes no difference.

In my case, I had no choice. I either provided the mandatory level of quality, or I had no customers. I think that's the part that was hard for me to grasp at first, but having read the comments of others since joining this group, I can see, clearly, that they have concepts that suit them as well as mine did me. What's important is to refine, regardless of the level of quality.


A comment about sue.

I really didn't mind that guy. If anything, I found him amusing. I had his number early on, however, and was the cause of my calling him out. If readers didn't notice, his method of operation was to cast doubt on information posted. I'm not here to tell you that everything that I say, or that others say, is always dead on, but we have enough experience to bring along a guy that has never refined and have him producing gold of acceptable quality, that being his desire. We can't have a reader, masquerading as a refiner, tossing a wet blanket on tried and proven information-----even if there's better processing out there. The point is, what we talk about and do works, and works quite well.

Had sue come from a different vantage point, whereby he posted his comments, then offered an alternative, that would have been a totally different kettle of fish. He didn't do that. Not even when asked. I'm not convinced he could.

Harold
 

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