How do you tell the difference between gold and brass coins?

A. There must be coin dealers and jewelers in Denver who can answer this question "by eye" almost before you cross the threshold of their shop, Cynthia, but who can test it instantly if need be.

The simplest test for you would be a weight test; gold is much heavier than brass, well over twice as heavy, 19.3 g/cm for gold vs. the vicinity of 8.5 g/cm for brass, depending on composition. Look up "Archimedes displacement experiment" if you don't quite understand. Good luck.

A. Try muriatic acid ⇦this on eBay or Amazon [affil links] , if its a gold coin it will not be damaged, if its brass, well who cares...it wasn't gold anyway.

A. For small metal objects specific density is very good test.

You need only precise balance.
1.weigh object in air
2.weigh object submerged in distilled water
3.Calculate density

(mass in air)X(density of liquid)
-------------------------------------
(mass in air)-(mass submerged in liquid)

4.Compare values: pure gold=18.88, gold 18K (light yellow)=15.4, gold 14 K (yellow)=13.6, brass(yellow)=8.40-8.55, water=1.00(20 °C temp.)  

Good luck!

A. Density. Gold is much denser than brass.

A. Open an old fashion car battery (unfortunately the new ones come sealed). Wrap a small piece of cotton or rag over a long wood or plastic stick, take out some "battery acid ⇦this on eBay or Amazon [affil links] " and touch the coin. If no change in color or reaction, it is gold (or at least a very good and thick gold plate). Surest method remains the density check.

A. Take your coin to a pawn shop. They will know the difference.

A. The simplest way employed by many jewelers is to rub the brass object between or with your fingers. Brass has a unique smell which will be transferred to your fingers and can be easily detected. Conversely, rubbing a gold object with your fingers produces no smell at all.

Grr, me too, brass or gold ... I shall also try to find out whether or not my £2 coin is brass or gold using the methods you have provided, thanks people :)

A. Gold doesn't tarnish. Gold is much more dense than brass, but it has the same exact density as tungsten. Nitric acid dissolves almost every metal and alloy except for gold. One can also tell the difference in colour. Brass is pale and has a yellow tint to it. I hope this helps.

A. Rubbing it between your fingers is the best way to tell if it smells like any thing its not gold!

A. First wash the coin or small object you want to test with warm soapy water and dry very well. Very simply but carefully put the coin on the top middle part of your tongue and close your mouth, take a deep breath and taste it, if the coin has a funny taste it is not gold as gold will have no reaction with taste or smell in your mouth, other metals will, even brass but if you have any doubts to whether it is brass or some other metal you may not want to do this. Good luck, God Bless and don't swallow the coin :)

I bought a crystal ball paperweight with a gold colored cherub on top. I wanted to know whether it was brass or not. After reading many different tests, I decided on the "rubbing between your fingers" test. IT WORKED! My fingers had the most distinct smell after. Now I know it's brass! Thank you for the help in solving my problem.
Sincerely,

A. Hi Dorothy. Sounds like brass to me :-)

If it's not steel/iron as demonstrated with a magnet, the only other thing it would likely be is aluminum -- and aluminum should be very light, and would be unlikely to look like dirty copper on the inside.

Regards,

A. That one is easy, Elizabeth: they're not gold :-)

But if you want to check, there are already many good answers on this page, but check the density like Archimedes did --

Put the knob in a cup of water that was filled to the brim and capture the water that spills over and weigh it. Weigh the knob and divide by the weight of the water it displaced to determine its specific gravity. If the knob weighs 19.3x as much as the water, it's gold. If only 8.5x as much, it's probably brass. The difference is so great that there should be no ambiguity at all. Good luck.

Regards,

A. The test is so simple that mass displacement is not necessary. To test gold from brass, even plated brass will show this is up, is to take an eye dropper of silver nitrate and of course the drop will change the area to pure silver. You know that old electron theory right? Silver nitrate will change gold to silver, but it is for earned a oneway trip. You cannot create gold with any molecular mix.

A. Update on the Silver Nitrate, I recommend actually no more than one drop. The silver will wear away because it is the depth of Atomic in nature. I realize that it is not easy to get silver nitrate , check with your local jeweler and there is the importance, whether you want a coin to remain uncirculated, you cannot touch it. Also Gold does not tarnish like brass. Brass will dull to a greyish color and Gold will remain its yellow color. But the thought added here is that a brass coin has a specific tone when dropped on say a Formica surface as opposed to a gold coin will have a higher pitch. But alas if you're just selling it for its element, then you will find gold scratches and bends easier then brass.

Anthony Nugey [returning]
- Linden, New Jersey, USA
December 2, 2011

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 Hi Anthony. There are typos in your first response, but I'm not sure quite where. I think the thrust of it is that silver nitrate will not create a silvery deposit deposit on gold.

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

April 8, 2013

A. Hi Jennifer. Please google "Marine security guard detachment" and you will understand what this is. You didn't exactly ask a question, and you say you've read the suggestions for telling brass from gold, so I'm not positive what you want from us at this point except this answer: it's not gold :-)

Although it has no value to anyone else, it probably has strong sentimental meaning to someone who served our country in Chengdu, so I'd urge you to put a note on the bulletin boards of stores or meeting places near where you found it.

Regards,

But a really easy way to know that something isn't gold is the Archimedes weight test. Weigh the nuggets, then put them into a glass of water filled to the brim placed inside a dish that will catch the spillover. Divide the weight of the nuggets by the weight of the spillover and you have the density of the nuggets. As noted earlier on this page where we appended your inquiry, gold is about 19.3 times as heavy as water and brass is only about 8.5 times as heavy as water.

There are other heavy things which this test doesn't rule out, but the difference between brass and gold will be dramatic. Good luck.

Regards,

A. The best answer is take a pencil torch or house hold torch to it and if it discolors it's brass get it glowing red if it melts it's gold if it turns colors it's brass as the question stated home test ,not buying anything and easy those things considered I feel that would be the best answer however if it's a valuable coin you don't want to melt or warp it but the test could be done with care not to do either.