Is My Math Correct For Inquarting Gold With Silver?

[Anonymous]

Hello members,

I'm doing my first inquarting of gold and I'm wanting to make sure I did the math correct. I have read some tutorials here and read the calculations, but I actually used the calculator from Samual-a web site. I'll learn it soon without a computer, but for now, this is helping me understand the ratio of base metals to the pure gold content.

Never mind the gold value as I did the copy/paste about an hour ago. I just want to make sure I'm learning to understand the right ratio of silver for inquarting. Also, should I hold on to the white gold ring or inquart it with the rest of the gold? I also added a gram more silver to the calculations to make sure I'm close enough.

14K Teeth Plate: 4.97g
Pure Gold Content: 2.8975099999999996 Grams
Gold Value: 137.99574198630353 Dollars

14K (White Gold) Ring: 1.77g
Pure Gold Content: 1.0319099999999999 Grams
Gold Value: 49.14536485226505 Dollars

10kt lot- 4.6g
14 April 2013 20:02:06
Pure Gold Content: 1.9135999999999997 Grams
Gold Value: 91.13640742050603 Dollars

18kt lot -1.7g
Pure Gold Content: 1.275 Grams
Gold Value: 60.72267948429411 Dollars

14kt lot -0.3g
Pure Gold Content: 0.17489999999999997 Grams
Gold Value: 8.329722856316108 Dollars

==================================TOTAL 13.34 grams================================

==================================TOTAL PURE GOLD 7.27 grams======================

22.88 grams of pure silver to inquart the gold.


Is the math correct?

Thanks

Kevin

 

[Anonymous]

After going back over everything and rereading the page on Samuel-a's website, I noticed the below information. Is that correct for 10K?


10 karat gold - item contains 41.66% gold and 41.76% another metals (used for jewelry).

I read this on e-How just a short while ago.

10K Gold

Gold designated 10K contains 37.5 percent pure gold and 62.5 percent other metals. Metal of less than 10K gold content cannot be sold as "gold" in the U.S. A typical 10K gold alloy contains 37.5 percent gold, 52 percent silver, 4.9 percent copper, 4.2 percent zinc and 1.4 percent nickel. "Rose" 10K gold contains a higher percentage of copper and slightly more gold, lending it a reddish cast.

Kevin

 

[Palladium]

Your numbers are correct.
13.34 grams - 7.27 grams of 24 k gold = 6 grams of base metal already included.
You have 7.27 grams of 24 k so multiply that X 4 to get the gold to 25% = 28 grams.
You have 6 grams already so you need to add 22 more.

Sam had a misprint on his website i see. 10k = 41.7% gold and 58.3% base metals.

 

[Anonymous]

Your numbers are correct.
13.34 grams - 7.27 grams of 24 k gold = 6 grams of base metal already included.
You have 7.27 grams of 24 k so multiply that X 4 to get the gold to 25% = 28 grams.
You have 6 grams already so you need to add 22 more.

Sam had a misprint on his website i see. 10k = 41.7% gold and 58.3% base metals.

Palladium, you always make me feel better about what I do when you chime in. I really appreciate your help and guidance. My only obstacle now is to take imaginary gold samples and pretend I have x amount of 14K and x amount of others, then do the calculations on paper or calculator. Once I do that, I'll know how to do the math correctly without having to ask questions (even though I have been reading Hoke's Book and the forum threads on the inquarting). Some things just don't click in right away for everyone at first.

Thanks again my brother.... you gave me much more hope on my calculations. :mrgreen:

Kevin

 

[Harold_V]

Your numbers are correct.
13.34 grams - 7.27 grams of 24 k gold = 6 grams of base metal already included.
You have 7.27 grams of 24 k so multiply that X 4 to get the gold to 25% = 28 grams.
You have 6 grams already so you need to add 22 more.

Not quite.
The goal is for 25% gold content (for inquartation, or *quartering*).

In order for the equation to be correct, you must include the gold-----so the total weight after inquartation would be 29.08 grams.
From the 29.8 grams you would deduct the 13.34 grams, leaving you with 15.74 grams of silver to be added.

Want to check the figures?

Simple.

15.74 grams silver added to
13.34 (the alloy you intend to refine)
------
29.08 grams x 25% = 7.27 grams of pure gold.

Because of the sheer volume of gold I processed, all done without a preliminary assay, I concluded that the addition of 110% of the starting alloy weight would be quite close to the desired ratio. It won't be enough if you're processing all 14K or better, but with mixed alloys, it tends to be quite reliable. Remember, it's not critical, as a gold/silver alloy will part through a fairly broad range.

Harold

 

[Palladium]

I'll be dam! You are exactly correct Harold. I understand my mistake now! So actually i have been over calculating the silver on the high side anyway which is a good thing i guess, especially with higher karat gold. I love being corrected because now i know.

 

[Anonymous]

Harold_V,

Thanks for the correction and explanation. I understand the calculations more so now. Here's how I made it easy for me to remember....

13.34 grams of total metal to refine.
7.27 grams is pure gold.

I multiply the pure gold by 4 (7.27 x 4 = 29.08) (29.08 is the total the metal should be after adding the silver.)

I take 29.08 and subtract the total weight of the metal to refine (13.34) and I'm left with 15.74 grams. The 15.74 grams is the amount of silver I need to add to the metal to inquart.

It's much easier now that I understand the calculations better.

Also, I noticed that when I looked at a few tutorials here on inquarting, it appeared to me that if a person added between 100 - 110% of the weight in silver, they would be close to the ratio needed. Although it's not exact, but that's how I kept figuring it out when I did the math.

Thanks so much for clarifying this for me, and hopefully it'll serve to help others too. And I thank you too Palladium for your help.

Kevin

 

[Anonymous]

I just now finished inquarting my gold and here are the results.

29.08 grams total weight.
28.48 grams after inquarting.
0.6 grams loss during melt. M.A.P.P. torch was used. Maybe I'll try the propane next time.

This was very interesting to do. I got the hang of it now.

Thank you all for this great site.



Kevin

 

[Emryst]

I just now finished inquarting my gold and here are the results.

29.08 grams total weight.
28.48 grams after inquarting.
0.6 grams loss during melt. M.A.P.P. torch was used. Maybe I'll try the propane next time.

This was very interesting to do. I got the hang of it now.

Thank you all for this great site.

View attachment 20706

Kevin

This posting is from some time ago but if it's still being read. I would like to know if I'm correct in thinking the .6 grams lost is in silver as it has a lower melt temp so it can vaporizer during the melt. Is this logic correct?

 

[4metals]

Generally with karat alloys the gold silver and PGM's will not volatilize, nor will the copper. Lower temp melting metals like zinc and some of the metals used in dental alloys will volatilize but not the precious metals that were metallic to start with.

 

[nwinther]

Generally with karat alloys the gold silver and PGM's will not volatilize, nor will the copper. Lower temp melting metals like zinc and some of the metals used in dental alloys will volatilize but not the precious metals that were metallic to start with.

Some tiny amounts of metal would probably stick to the melt dish or crucible as well?

 

[4metals]

Some tiny amounts of metal would probably stick to the melt dish or crucible as well?

Nothing that cannot be recovered later or seriously limited with the right flux blend.

 

[nwinther]

Nothing that cannot be recovered later or seriously limited with the right flux blend.

Agree, but in the immediate control on the scale it would be missing. Probably not in the amounts mentioned (2%).
Gunk/dirt on the silver/gold burning off?

 

[nickvc]

If you have just very clean metals no dirt or stones when you melt you may see some loss but the precious metal percentage will increase in the resulting bar.
Many years ago we supplied 9k casting grain to a trade casting house on behalf of our customer , been in the UK we always alloyed at 376 the assay had to be 375 at least to pass hallmarking rules, well our customer had a large batch of castings returned as under assay and we reckoned that someone had worked out that they could take some grain out and add a little copper and it should still be ok as there would be some loss during the melting process and that the grain was above assay already but they got too greedy and stole too much.

 

[4metals]

Agree, but in the immediate control on the scale it would be missing. Probably not in the amounts mentioned (2%).
Gunk/dirt on the silver/gold burning off?

Answering questions about refining losses needs to address the size of the lot melted. While a 2% loss on a 100 ounce lot would be a serious loss, a 2% issue on a lot of 13 grams as described in the original post would amount to about 1/4 of a gram. Easily explained by dirt and body oils that contaminate a lot of used jewelry.

In a refinery the melt is usually weighed before and after the melt and percent loss is calculated. A good melt shop will note if the lot smoked a lot indicating zinc burn off or the soils burning off. Melt losses in the range of 1/2% are typically considered normal for scrap karat.

 

[4metals]

we reckoned that someone had worked out that they could take some grain out and add a little copper and it should still be ok as there would be some loss during the melting process and that the grain was above assay already but they got too greedy and stole too much.

I knew a contractor 30 years ago in NYC who took clean alloy and rolled it into plate and wire for the jeweler he was working with. He would typically work with 50 ounces or more and make it into the product of the desired diameter or thickness. Turned out he would add an ounce of copper to the alloy before casting it into the molds for the mill and at the end he would cut off an ounce of finished product.

This was long before XRF was on the scene so the owner of the alloy came to our refinery and asked us to melt his alloy into a bar and assay it before he gave it out for rolling. Then he brought back samples of plate and wire and sure enough it had lost a percentage of the gold. This was easier to get away with before the "instant" assay an XRF provides.

 

[nickvc]

Well in the UK the hallmarking laws are very very strict and they will not mark anything under carat by even 1 point , there are a few exceptions with 18 white , 22 carat and platinum been the main ones as the solders used wouldn’t work at full .
Unfortunately there have always been a few on the make at others expense and if the marking rules are relaxed then it’s so much easier to do, it’s not as easy in the UK although we did have one customer that had if I remember 3 carat sheet and wire made to make earring stampings that were below the hallmarking requirement weight he was always up to no good he even did the customs and excise for loads of money…

 

[nwinther]

Answering questions about refining losses needs to address the size of the lot melted. While a 2% loss on a 100 ounce lot would be a serious loss, a 2% issue on a lot of 13 grams as described in the original post would amount to about 1/4 of a gram. Easily explained by dirt and body oils that contaminate a lot of used jewelry.

In a refinery the melt is usually weighed before and after the melt and percent loss is calculated. A good melt shop will note if the lot smoked a lot indicating zinc burn off or the soils burning off. Melt losses in the range of 1/2% are typically considered normal for scrap karat.

In theory the weight of the melt wouldn't matter. Only if you account for outside factors such as pits in the crucible being filled, traces of gold remaining in solution or whatnot, the relative amount of gunk on ½Ozt or 100Ozt would be the same.
(BTW 2% is the .6 grams loss - all the gunk could be on the silver used for inquarting meaning no gold loss.)

 

[4metals]

(BTW 2% is the .6 grams loss - all the gunk could be on the silver used for inquarting meaning no gold loss.)

I guess this all depends on what the source is for your Silver used to inquart. Clean cemented Silver, well rinsed, does not usually have the soils that jewelry which has been worn has, and the Silver and small percentage of Copper will not volatilize. But if it is not dry you will be weighing moisture that will not be there when it is melted.