# Plz Help Through Air weight & Water weight how to calculate



## sohailag (Sep 28, 2011)

Dear Brother,

Please Help me,

I have gold bar how I calculate actual pure gold in this bar.

Air weight & water weight.

Any brother give me any formula. I search the web found the specfic gravity gold test method but its not right. Its give the wrong result. 

Please Help me in this .

Thanks in advance.

Best Regards,

Sohail


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## butcher (Sep 28, 2011)

how could it give you wrong results? it is a simple formula, and proceedure.

is it that it does not give you the result's you want to see.

is it possible that your metal is not as heavy as you wish?

what are you trying to get the specific gravity of rock, metal bar?

maybe post your proceedure, with full details,and maybe we can see what your doing wrong or if there is a better way to test your material.


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## sohailag (Sep 29, 2011)

This is the Formula I get from different sources;

Note the weight of the specimen (wet weight).
Now you have the dry weight and the wet weight of the specimen. Use the following calculation to calculate the amount of gold in your specimen.
- Subtract the wet weight from the dry weight and note the difference (D).
 - Divide the dry weight by (D) and write down the result (SG) which is the specific gravity of the specimen.
 - Subtract the specific gravity of quartz (2.60 to 2.65) from (SG) to get the result (R).
- The specific gravity of quartz varies from 2.60 to 2.65 because some quartz is more dense than others. This variation does not affect the result greatly, but it does show that the calculation, though close, will never be 100% accurate. 
 - Multiply the result (R) by (D) to get a result (R2). 
 - Divide (R2) by 25.97, which will give you the contained amount of gold in the specimen in ounces. 
 - Multiply the contained amount of gold in ounces by 31.103 to get the contained amount of gold in grams.

Below is an example using the formula above:

Specimen dry weight: 35.8 Grams  Specimen wet weight: 27.9 Grams  35.8 minus 27.9 equals 7.9 Difference (D)  35.8 divided by 7.9 equals 4.53, the specific gravity of the specimen (SG)  4.53 minus 2.63, the average specific gravity of quartz, equals 1.9 (R)  1.9 (R) multiplied by 7.9 (D) equals 15.01 (R2)  15.01 divided by the constant 25.97 equals 0.577 ounces of contained gold  0.577 ounces multiplied by 31.103 (the number of grams in a troy ounce) equals  17.94 grams of contained gold in the specimen.

I also make this formula in excel & upload it for users testing & correcting error mistake.

Please Help me My main purpose is this when I am melting mixed old products of gold of purities after making a shape of Bar before Refining I get the idea of much pure gold in this bar.

Thanks in advance.

Best Regards,

Sohail


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## eeTHr (Sep 29, 2011)

Since you have gold bars, why would the specific gravity of quartz be needed?


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## sohailag (Sep 29, 2011)

Dear brother,

I tell you again these gold bars are not pure I melt a old Jewellery
Of different purifies like in my country 21kt, 19kt, 18kt after melting
All together & make a shape of bar before refining how I calculate
How much pure gold in this mixed Jewellery melted bar.

I hope you understand.

Thanks for reply. Still waiting for solution.

Best regards,

Sohail.


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## Palladium (Sep 30, 2011)

You just have to love this.  

http://www.midstatesrecycling.com/karat_kalc


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## eeTHr (Sep 30, 2011)

sohailag---

Since the formula you posted involves quartz in it, it appears to be for use on _*ore.*_

My point was that since you have karat gold, and not _*ore,*_ including the figures for quartz may be where your error is coming from.

Getting the specific gravity for a bar is not that complicated.

There are two ways to do it.

1.) The specific gravity of a solid is the ratio of its weight in air to the difference between its weight in air and its weight immersed in water.

If you have a hanging spring scale, where you hold or hang the scale up, and it has a hook or recepticle to weigh the bar on, hanging from the bottom, then use this method.

2.) If you don't have a hanging spring scale, use the method for liquids, but determine the volume by the displacement method, below.

The volume of a solid with uneven surfaces is difficult to measure, so water can be used to measure it's volume, by displacement.

Either use a graduated container, or mark your own graduations, as follows. Put enough water into your empty container to easily cover the bar when it is placed into the container with the water later. Mark the water level on your container, then add a known amount of water, like 100 ml, and mark the new level on the container. Keep doing this until you have enough graduated marks that you can see will be more than the volume of the bar, as the water will rise that amount when you put the bar in.

Then remove the water you added, down to the first mark on the container.

If you have a container that is already graduated, put enough water in it to easily cover the bar, and come up to major graduation mark.

Set your bar on the bottom of the container with the water, and see where the new water level is. The difference between the water level without the bar, and the new level with the bar, equals the volume of the bar. Then go directly to step #3 in the above link, and substitute "bar" for "liquid," and do only steps #3 and #4.


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## sohailag (Sep 30, 2011)

Dear Brother,

I get the formula from web but I mistake about quartz I realize.

You are right I check the links you send me. These links are useful but I am confused Sorry I am NEW in this please explain me I found this formula useful.

Specific gravity is a comparison of a substance's density to that of water. Water's density is 1 gram per cubic centimeter (1 g/cm[3]). The specific gravity of a substance is determined by dividing its density by that of water. Because specific gravity is determined by dividing two densities, the units cancel each other out, and the final value is given with just a number. Specific gravity can also be calculated by dividing the weight or mass of an object by the weight or apparent mass of the same object when it is submerged in water. Because each substance has a unique specific gravity, this test can determine the composition of an object. (I test this one)
Difficulty: Moderate
Instructions

Things You'll Need
Spring scale
Measuring cup
Water
◦	1 Weigh your solid by hanging it from the spring scale. 
◦	2 Fill the measuring cup with enough water in which to submerge your object. 
◦	3 Hang the object from the spring scale and lower it into the water until it is completely submerged. Record the weight of the object when in water. 
◦	4 Divide the weight of the dry solid by the weight of the solid when it was submerged in water. The result is the specific gravity of the solid. 

(I have the weight scale for dry & water weight)
Now for example.
I have a Dry weight 65.560
I have water Weight 61.800
I divided weight of the dry to weight of the air
65.560 / 61.800 = 1.060 Answer specific gravity of solid

Now What's Next can I divided 65.560 to 19.3 - 65.560 = 62.163 is pure gold I am right or wrong?

Please Help I am waiting Brother.

Thanks in advance.

Best Regards,

Sohail


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## eeTHr (Sep 30, 2011)

sohailag---

Specific gravity is the ratio of the weight of a sample (in this case, your bar), to an equal volume of water.

The density ratio of gold:water is 19.32:1. This represents a Specific Gravity of 19.32.

If the specific gravity of your bar is only 1.06, then it is only 0.31 % of the density of gold. It would be a non-metallic substance, so I think your weights are wrong. It looks like you added an extra zero between the decimal point and the six.

The formula should go like this, using 1 Troy ounce of pure gold, as an example---

1.) Dry weight of sample is 31.10348 grams.
2.) Weight of sample suspended in water is 1.60991 grams (this is actually the weight of the displaced water).
3.) 31.10348 divided by 1.60991 = 19.32 Specific Gravity.

The technique of suspending the bar in water, gives the weight of the displaced water, not the weight of the bar. This allows for the division step to calculate the _*ratio*_ of the weight of the bar to the weight of the equal (displaced) volume of water, and thus arrive at the Specific Gravity figure. The bar cannot touch the bottom or sides of the container.

You can also get the weight of the displaced water by suspending a bar into a container of water, on a regular scale, as shown here. This link also has calculators for figuring the amount of gold, when it is in combination with another mineral, but *only if the other material in it is known.*

If you want to determine for your own reference, approximately how much gold your bars contain, you could take a small sample, weigh it, then dissolve it and selectively precipitate just the gold, then weigh the resultant gold to figure a percentage by weight. The purity of the resultant gold would determine the accuracy of your calculations, and the extent of your refining techniques would determine how pure you could be getting the precipitated gold powder.

But to be most accurate you would need an assay.



Edited for correction---

If suspending from a scale, you get the weight of the bar, less the weight of the displaced water, so you need to subtract the "wet" weight from the "dry" weight, to get the weight of the equal volume of water which is displaced.

If you have the water container sitting on the scale, the difference in weight, with and without the bar suspended in it, is the weight of the equal volume of displaced water.


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## eeTHr (Sep 30, 2011)

sohailag---

One more thing.

The standard for the water is 39 degrees F (4 degrees C) at 1 atmosphere of pressure, so water at that temperature and pressure would have a specific gravity of 1.

ref: Ways to Measure Specific Gravity.

Edit: As pointed out in samuel-a's link, below, the bar should be at the same temperature as the water, too.


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## samuel-a (Sep 30, 2011)

http://www.goldrefiningforum.com/phpBB3/viewtopic.php...


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## sohailag (Oct 3, 2011)

Dear Brother,

Sorry for the late reply I am out of my city to for office work.

Now I am Back.

I got it What you say. But hot to get displaced water weight.

I see video at you Tube about how to get water weight here is the link.

http://www.youtube.com/watch?v=GF4NqIYh6zg&feature=player_embedded

I also see the other place about this How they calculate the formula like this.

Weight in air - Weight in water = Weight difference

Weight in Air / Weight Difference = Answer is the Density of the object.

I get this this formula from here.

http://www.platinumguild.com/files/pdf/V3N6W_practical_applications.pdf

But the result is not right.

In your formula can you Explain Brother how I get displaced water weight.
Sorry to disturb you again & again but I am new Your Help is appreciate me to go in this field further.

Thanks in advance.

Best Regards,

Sohail


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## eeTHr (Oct 3, 2011)

sohailog---

Due to the _*buoyancy*_ of the bar, the weight measured when suspending it in water _*is*_ the weight of the displaced volume of water. No further conversion is needed.

Thus, when you divide the weight of the bar, by the weight of the displaced water, you arrive at a *ratio* of the weight of the bar to the weight of an equal volume of water. This ratio is the specific gravity (which is, by definition, a ratio).

Pure gold will have a weight ratio, to an equal volume of water, of 19.32-to-1.

If your bar is close to that, and *you're sure* there is no tungston, or other heavier than gold metals, in it---then you have relatively pure gold.

If less than 19.32 specific gravity, then you would need to know that there is only one other metal in it, and what that metal is, in order to caluculate exactly what percentage of it is gold.

If the specific gravity is more than 19.32, then you have platinum, or other heavier than gold metal, in your bar. And again, if you know for sure that there is only one other metal present in it, and you know for sure what that other metal is, then you can calculate the percentages of gold and that other metal.

If you use the method of hanging the bar from a scale, be sure to either reset the scale to zero (tare) with the hanging device attached, or subtract it from the final weight when the bar is suspended in water. If you use the method of sitting the water container on a regular scale, be sure to subtract the weight of the container and water from the final weight with the bar suspended in the water.


If you are wondering why the suspended bar weight is the weight of the displaced water, it is because when you _*suspend*_ the bar in the water, you are not adding the _*weight*_ of the bar to the water, you are only adding the _*volume*_ of the bar to the water. It is the same as if you just added a volume of water equal to the volume of the bar. You would get the same weight reading on the scale, whether the bar was gold or aluminum, as long as both bars were the exact same size.

The weight of the bar itself, only counts when you weigh it "dry."



Edit for correction---

If suspending from a scale, you get the weight of the bar, less the weight of the displaced water, so you need to subtract the "wet" weight from the "dry" weight, to get the weight of the equal volume of water which is displaced.

If you have the water container sitting on the scale, the difference in weight, with and without the bar suspended in it, is the weight of the equal volume of displaced water.


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## sohailag (Oct 4, 2011)

Dear eeTHR,

I understand the buoyancy of the bar.

But I have the bar with mix mixed impurities I melted mix used gold jewellery of different karrat like 21kt, 19kt, 18kt these all jewellery are mixed with siver & copper mixing
now after melting these old gold jewellery with shape of bar you no how I get the water weight as you see in youtube video & I have Air weight now how I calculate the weight of pure
gold in this bar. My 2 friends have the formula when I get my melted bar to them they just get the air weight & water weight & give me the idea how much pure gold in this bar but they don't tell me the formula.

So your help appreciate me to read different formulas & research its increase my knowledge but I am at still same place at very first day. I hope you understand me. 

Its very thankful to you guide me how I Calculate the things.

Thanks in advance,

Best Regards

Sohail
:idea: :roll: :?: 


Best Regards,

Sohail


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## goldsilverpro (Oct 4, 2011)

sohailag said:


> Dear Brother,
> 
> I get the formula from web but I mistake about quartz I realize.
> 
> ...



In your example, the SG = (weight in air)/(weight in air - weight in water) = (65.560)/(65.560 - 61.800) = 65.560/3.76 = 17.4

Since the various percentages of the non-gold alloying ingredients (copper, silver, zinc - all of which contribute differently to the overall SG) in karat golds can vary considerably, depending on the exact color desired by the manufacturer, the SG method can, at best, only give an approximation of the gold content.

Also, to get decent accuracy when weighing, the scale you use should provide at least 3, and preferably 4, significant digits.


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## eeTHr (Oct 4, 2011)

GSP is right.

I misstated part of my previous post, in that the weight is figured differently, depending on whether you are suspending the bar from a scale, or if the water container is sitting on a scale and you are suspending the bar into it.

If suspending from a scale, you get the weight of the bar, less the weight of the displaced water, so you need to subtract the "wet" weight from the "dry" weight, to get the weight of the equal volume of water which is displaced.

If you have the water container sitting on the scale, the difference in weight, with and without the bar suspended in it, is the weight of the equal volume of displaced water.

It sounds like your friends are using an estimated average of the specific gravities of the various possible alloys of added base metals. One reason for learning to refine is to make sure you are getting paid correctly.


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## goldsilverpro (Oct 4, 2011)

sohailag,

Go to this link advertising the book I wrote and click on the 1st pdf attachment in the 1st post on the thread. At the bottom of page 41 you will see a chart of several karat gold alloys in various colors. Please note the variations in the percentages of the alloying metals and the resulting variations in the densities (specific gravities). For example, some typical alloy compositions of 18K yellow gold are: Copper - 5% to 15%; Silver - 10% to 20%; Zinc - 1% to 3%. The range of the densities of these variations is from 15.1 to 15.7, although they all contain 75% gold and all are yellow. Therefore, it is impossible to calculate the exact gold percentage from specific gravity measurements, unless you know the exact percentages of the alloying ingredients. However, if you knew these percentages, you would also know the gold percentage, by difference, and the measurement of the specific gravity would therefore be a moot point. Another thing that could produce error would be when the bar contains gold solder.

http://www.goldrefiningforum.com/phpBB3/viewtopic.php?f=84&t=5810

If you really want to know the gold content of the bar, either sample it correctly and run a triplicate fire assay or, refine it.


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## sohailag (Oct 7, 2011)

Dear Gold & Silver Pro & eeTHR,

Sorry for late reply I just do the practical that's why I am late.

Your formula is right I get the accurate result. But for accuracy you are right I must need the balance with 3 or 4 decimal.

But one thing more I get the plain tap water. Its right to get plain tap water or get distolled water & one thing more for accurate water weight
I get any special bowl like plastic, metal or glass & big or small one an suggestions are appreciate.

Once Again very thank full to all brother who support me & other users. Thanks to team of Gold Refining forum & 2 my best supporting friends
Gold & Silver Pro and eeTHR.

Thanking you,

Best Regards,

Sohail


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## goldsilverpro (Oct 7, 2011)

sohailag said:


> Dear Gold & Silver Pro & eeTHR,
> 
> Sorry for late reply I just do the practical that's why I am late.
> 
> ...



For accurate work, tap water should not be used. Also, the temperature of the distilled water you use can affect its specific gravity and, for greatest accuracy, this would enter into your calculations. However, since the alloys can vary, the accuracy will be unreliable, even if your procedure is perfect. There are much better methods available. A simple scratch/acid test on a touchstone is more reliable.


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## danib (Jul 30, 2012)

Dear All, 
I have quite a similar problem that you answered so many times But Still I find no other option but asking for your help. I have been asked to develop a software to test gold purity. We don't know anything about possible metals and their combination alloyed with that particular gold bar. But still they are using this software for testing gold purity commercially in Gold test laboratories. I am sending you few calculations.
First Calculation:
First Weight (Dry Weight) 7.808gm
Second Weight(Suspended spring scale in water) 7.384gm
Total Impurity 0.3368gm
Total Pure Gold 7.4712gm

Second Calculation:
First Weight (Dry Weight) 10.3340gm
Second Weight(Suspended spring scale in water) 9.783gm
Total Impurity 0.3365gm
Total Pure Gold 9.9975gm
Carats: 23.2185K

Any help will be greatly appreciated.

Regards
Danib


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## Dan Dement (Jul 30, 2012)

Sohail,

I got an easy answer for you. Buy an Alpha Mirage SG scale and it figures the purity for you. Weight it n Air, drop it in the water, push a button and it figures the SG, Gold Purity, and has different alloy charts already figured into it. I have two of them and when in a solid melted mass, are pretty darn accurate. I have two and made a group purchase of 20 of them for friends. I know, all the guru's are going to say they don't like them but I will tell you, it's usually accurate to within 1%. I am on my third bigger XRF machine and have #4 on it's way. Yes, you can fool it but you can fool an XRF machine also. It's just real hard to fool both of them at the same time.

Dan


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## ericrm (Jul 30, 2012)

danib said:


> Dear All,
> I have quite a similar problem that you answered so many times But Still I find no other option but asking for your help. I have been asked to develop a software to test gold purity. We don't know anything about possible metals and their combination alloyed with that particular gold bar. But still they are using this software for testing gold purity commercially in Gold test laboratories. I am sending you few calculations.
> First Calculation:
> First Weight (Dry Weight) 7.808gm
> ...





sohailag said:


> Dear brother,
> 
> I tell you again these gold bars are not pure I melt a old Jewellery
> Of different purifies like in my country_* 21kt, 19kt, 18kt*_ after melting
> ...



i know that there is obviously a language issue here
if you melted karat gold why do you expect 95%gold??
did you weight yourself your item in the biggining ?if yes you should be able to calculate you gold amount
if not ,why not to remelt everyting mix well ,than do a test streak on your test stone (it is just melted karat gold if i do understand right)
and the last why do you need to know the amount of gold since you will refine it ,just weight it when its pure....


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## goldsilverpro (Jul 30, 2012)

danib said:


> Dear All,
> I have quite a similar problem that you answered so many times But Still I find no other option but asking for your help. I have been asked to develop a software to test gold purity. We don't know anything about possible metals and their combination alloyed with that particular gold bar. But still they are using this software for testing gold purity commercially in Gold test laboratories. I am sending you few calculations.
> First Calculation:
> First Weight (Dry Weight) 7.808gm
> ...


I just noticed that you posted the exact same question on finishing.com.
http://www.finishing.com/189/07.shtml

You haven't stated your question very well. Were the figures you gave above obtained by your own measurements or from the software? What exactly do you want to know?

I should add that, unless you know all of the metals alloyed with the gold and their percentages, errors will exist in the results. Also, errors can exist due to the density of the crystalline structure produced by the alloying. I also would guess that the rate of cooling of the bar could affect this. Any software will have to make assumptions concerning these alloying ingredients, etc. Dan Dement, who posted on this thread, estimates the error in determining the gold content in gold alloy using SG will be about 1%. Dan has more experience in this, on a commercial scale, than anyone I know and what he says is very reliable.

I will give you some of the math on your first calculation. However, I have never seen a spring scale that would read to .001g. I may be wrong, but I doubt if they exist.


> First Weight (Dry Weight) 7.808gm
> Second Weight(Suspended spring scale in water) 7.384gm
> Total Impurity 0.3368gm
> Total Pure Gold 7.4712gm



The S.G. = (dry weight)/(dry weight - weight in water) = 7.808/(7.808 - 7.384) = 7.808/.424 = *18.415
*
Au = 7.4712/7.808 = .9568 or 95.68%
Impurities = .3368/7.808 = .04313 or 4.313%

Here's a way to *approximate* the S.G. when the percentages of all the metals are known:

*S.G. of a known alloy* = 100/{[(% of metal A)/(S.G. of metal A)] + [(% of metal B)/(S.G. of metal B)] + C.... + D...., etc.}

Assume the impurity is all copper. The S.G. of gold is 19.30 and that of copper is 8.90. Using your percentages:
S.G. = 100/[(95.68/19.30) + (4.313/8.90)] = 100/(4.958 + .485) = 100/5.443 = 18.37 g/cc

If the impurity was all silver (S.G. = 10.50):
S.G = 100/[(95.68/19.30) + (4.313/10.50)] = 100/(4.958 + .411) = 100/5.369 = 18.63 g/cc

The S.G. derived from your figures was 18.415 (above), which is in between 18.37 (Cu) and 18.63(Ag), but closer to the Cu. Therefore, if your numbers were from the software, it seems that the software assumes the impurities are made up of more Cu than Ag. I would not be surprised if the software utilized the above formula to generate its numbers.

I did your second calculation the same way and got similar results.

For approximating the S.G. of a known alloy, you might find this link easier to follow. Same results, though. Just a little variation in the math.
http://tmtpages.com/specific-gravity.htm

For this method, you don't need a spring scale. It could be improved on, though.
http://www.attilacoins.com/Calculate_Specific_Gravidity_coin.asp

For determining the gold percentage, the entire S.G. method is shot full of potential errors, unless you collect a lot of data (as Dan does) and continually compare the results with that of other methods (as Dan does).

The book I sell in my signature below includes a short chapter on evaluating karat golds using S.G., but I wish I had never included it. However, it was a different world back then. The gold price was about 1/5 of what it is today, the margin was generally larger when you bought from the public, and there was much less competition. You could be off somewhat and still make a decent profit. That's not necessarily true today. At least on a large scale, to be competitive, you have to be right on the numbers and you can't do that with S.G. unless you use it as just another comparative weapon in your arsenal, as Dan does.


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## Dan Dement (Jul 31, 2012)

GSP,

I have been a Gemologist for almost 40 years and SG is a factor in determing unknown gemstones so i am familar with the theory. I have been using the Alpha Mirage SG scale for about 5 years and have become friends with the Japanse owners. AS matter of fact, I just made a group purchase of over 20 of the latest scale for friends on another forum which has an accuracy into 3 digits meaning 57.1% of Gold. The latest scale is based on a 3 digit diamond carat scale so it is extremely accurate. I have just recieved as a gift from the owner of Alpha Mirage a printer which prints out figured Karat purity, Air Weight, Water Weight, Percentage purity, S.G., Temp. Variation, and SG variation on the printout tape. ( I will post this on WEdnesday as I home) . The scale has different Alloy Tables figured into the scale and you can change the table depending on the alloy. The most commom Tables are CA (Copper/Silver) and CU (mostly copper). In an average payout using the Copper setting which is the highest, I find the scale to be about 1% conservative. Now, it's really on accurate on solid melted ingot's and not hollow items. From memory, I believe todays 325 gram ingot had a figured SG purity of 55.3% and and Average of 7 XRF on my machine of 57.795 Average purity, I wwas paid by NTR at 57.9 for an $8.00 difference on a $8900 payout. I will post my workup sheet which has 7 XRF readings along witht eh SG printer tape.

One of the strongest points is that both agree. When you start adding metals like platinum, it throws the SG readings off as the 60% heavier weight will show the gold to be more pure and most refiners are not going to pay for small amounts of Pt. Pd slightly the opposite effect. It also works very well on silver as if silver is over 10.25 SG, you know that you probally have less pure silver as AG is usually has lead added to it. All the scale actually measures is the SG and the purity depends on the mixture of metals. It's a great double check for an XRF. i have seen the heavy plated Stainless gold chains that the XRF will call gold but the SG says it's 8,5 SG. You can fool one but it's tough to fool both.

Sometimes you need a gun, sometimes you a knife but it's always nice to have both! Tomorrow is a true test of an Old Man's ability, we are picking up my 2 year old grandson for two days. If I survive, I will post my last work up sheet with the XRF readings, the SG Tape, my calculations, and the NTR payout. It's not a fluke but i get this type of results almost everytime. I know it is not perfect and not a fire assay but not bad for a Texas Country Boy.

Dan


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## lazersteve (Jul 31, 2012)

Several years back, I had the opportunity to setup and test a digital specific gravity device that used water to determine the purity of gold and other metals. It was purchased by one of the local 'we buy gold' outlets that contacted me for technical advice on the calibration of the device.

It worked well, unless the item being tested had hollow space in it's structure. I suppose this is why Dan mentions melting the item to be tested. Air bubbles being trapped on the item also affected the accuracy of the reading.

When the device was being set up the first time, it had to have several baseline densities set in memory so that it could determine the purity based upon these stored numbers. If your stored values were off, then the accuracy of the purity would reflect the difference. You also had to check the ambient air temperature to get good results as changes in temperature affected the water density which would throw off the internal calibrations.

I liked the device despite the short comings it had with respect to accuracy and temperature variations. As things turned out the customer that had purchased the device ultimately returned it to the place where they had purchased it from. Thereafter the customer favored the scratch stone over the fancy device for determining the karat of unknown jewelry she was purchasing from her clients. The touch stone and acids where faster and provided enough accuracy to make her money at the margins she was buying gold.

Steve


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## Dan Dement (Jul 31, 2012)

Steve,

I greatly appreciate and respect your input and insight. I really have not had the pleasure of having a discussion with you but have read your posts and spent a little time on your website. I hold your viewpoint to and knowledge on the highest of levels. Is the SG scale the ultimate tool in a Gold Buyers toolbox, No! However, it was the first Gold Science toy that I bought. Understand, I think I have purchased most of the toys in the Jewelry Industry. Both of the Alpha Mirage Scales that I own, I use many times a day. The latest model, figures gold to third digit and is an excellent second opinion or cross check for gold buyers. I am not in the store today and have traveled to pick up my 2 year old Grandson. Tomorrow, I am going to post my work up procedure for selling my gold. Now, I usually melt metal before I buy from the customer by use of a small Wand Induction Melter. At that point, the SG scale is fairly accurate usually about 1% conservative. The entire process takes less than 10 seconds and it process a written tape printout. Today, 3RD XRF with SSD reader is a little more accurate but varies from point to point measured. 

All I have say is I bought over 20 of them in a group purchase for friends without complaints. I had a friend who wanted to buy one of mine. No thanks, I am keeping it. The entire set up is leveling, checking the water temp, calibrating with a Master weight. Every couple of days, I check the calibration with the Master Weight but I do that on all 4 of my scales.

More tomorrow and show everybody how I do it with teh payouts. I am sure not everyone is going to agree but it works for me.

Peace,
Dab


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## Dan Dement (Aug 1, 2012)

View attachment 3
As promised, this is my method of calculating a payout. I run seven XRF's readings and average them and compare that to my SG which is tape in the right corner. I show the Gold Wedge with the numbers that show where the XRF reading's are taken. I also show the payout from NTR. Now, no two XRF machines are going to read the same and I also do pin samples if necessary. I find this method to be a fair method in my mind and certainly a good basis to form a opinion for a cash out. I know many are not going to agree and I am always looking for better ways. It may not be right but it is what I use until I find something better. Please feel free to openly comment as you can't hurt my feelings.

Dan


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## Dan Dement (Aug 1, 2012)

I can't seem to get the NTR settlement to post so I am trying agian.

Dan


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## qst42know (Aug 1, 2012)

Dan Dement said:


> I can't seem to get the NTR settlement to post so I am trying agian.
> 
> Dan



Zero melt loss and zero silver?

Do they melt what you bring them or just shoot and pay for the gold only?


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## Dan Dement (Aug 1, 2012)

QST,
I am bringing them a super clean triangle which 90% of the time, they just XRF. I have seen them remelt my bars but after shooting and finding some differences. I must admit, out of 100 times, we have disagreed once. My bad, and they were correct. I did remelt and found somehow, XRF got it's calibration off. Someone must have pushed the wrong bottom which might have been me. Understand, that NTR has $100,000 XRF's and they run a two minute scan. My XRF has a SSD reader and I get very good accuracy at 20 seconds. Not that that any two machines agree exactly all the time. However, using this method, cashing out 2-3 times a week, we are usually in a $20. window up & down. I must also tell you, my Newest Big Buck XRF machine will be here August 15th. Always trying to improve!

Dan


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## lazersteve (Aug 2, 2012)

Dan,

Your method of determining the gold purity is much more accurate than what the client I mentioned in the above post was going for. All she cared about was that the final payout from Republic Metals made her a profit. Doing things the way you are is a much better insurance policy against losing profits due to inaccurate testing. 

I guess it all depends on what you pay your customers and what you expect to make in profits after the dust settles as to which method(S) of testing are right for you. The tighter your margins, the more accurate you must be.

Honestly, I really liked the water density device, it just turned out to be too much 'technology' for the individual I was working with.

Steve


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## Dan Dement (Aug 2, 2012)

Steve,

Thanks for your review of the process. I understand everyone looking for the easy button! I guess that's why I continue to search for the most accurate method for my purposes. The SG is the knife in the fight which can be very useful. The XRF is certainly more accurate but has it's limitations also. Getting a homogous mix is another very interesting subject. All I can say is that my process works fairly well for me. With gold on a mini-rollercoaster, I prefer to cash out every two days and my volume of business is not in the kilo variety. I am sure that in bigger quanities, new challenges would be incurred.

Thanks for your review,

Dan


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## goldtech (Dec 29, 2012)

sohailag said:


> This is the Formula I get from different sources;
> 
> Note the weight of the specimen (wet weight).
> Now you have the dry weight and the wet weight of the specimen. Use the following calculation to calculate the amount of gold in your specimen.
> ...



Dear Sohail,

This of ur Formula isn't for Gold. Beacause it is giving wrong result in gold calculation.


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