03-15-2012 10:22 AM
Lately I have found many instances of jewelry (particularly earrings, earring backs, and non-spring clasps, also some pendant bails) which are marked 10K or 14K and yet are attracted to a rare earth magnet. Rare earth magnets are admittedly a lot stronger than the older common magnets, so an old weak horseshoe magnet may not do much of anything, while a rare earth magnet causes that same piece of jewelry to leap in the air. But magnetic is magnetic, and I have been taught that gold and the usual alloy metals are NOT magnetic.
Returning such a piece to a seller on eBay frequently brings wrath on my head, as the seller is going by the mark on the piece and is understandably upset by being left “holding the bag”. So I've been doing my best to make inquiries of knowledgeable people about the issue, specifically, are there ANY alloys of gold which contain iron (would be magnetic), or is there any other legitimate reason a gold piece would respond to a magnet? Here's a summary of what I've found from putting the question to the International Gem Society forum, and also from an article on gold alloys written by Dr. A. M. Helmenstine, online at About.com Chemistry:
1) a clasp with a spring in it should not be tested this way as even a 14K circle spring or lobster clasp does have a tiny iron spring in it, and a magnetic response is OK there! But this objection does not apply to the fishhook type clasp which has no spring (often used on pearl strands) or other kinds of non-spring clasps.
2) 10K or 14K gold is of course not pure gold; it’s alloyed with other metals. For yellow gold, the other metals are likely to be silver and copper (NOT magnetic). For white gold the other metals may be platinum, palladium, zinc, and/or nickel. There is some question about the magnetic properties of nickel but the consensus seems to be that it can be considered nonmagnetic for this purpose. Thus the common colors of gold alloys have no reason to be attracted to a strong magnet, that I can find.
3) There is ONE gold alloy that might be legitimately magnetic. It’s “blue-white gold” (not common). 18K blue white gold is composed of 75% gold, 25% iron. (I have yet to find any to try it out with a magnet but if anyone else has, I’d love to know the result.)
4) The other less common gold alloy colors include purple (gold with aluminum), green (gold with silver and copper or cadmium), and rose (gold with copper). These also are not expected to respond to a magnet.
5) NOT being attracted to a strong magnet does NOT prove the gold truly is what it’s marked. The piece can be gold-plated or gold-filled (which is rolled gold on a base metal) and the underlying base metal need not be magnetic (copper, for example, is a common base metal in jewelry). You still need to do other testing.
6) If the piece IS moved by a magnet, there is probably iron or steel in the piece. One expert points out that iron is not normally an approved component of jewelry and that steel is probably involved where the jewelry piece is responding to a magnet. He states that even though bulk stainless steel isn’t magnetic, “all small stainless steel parts [become] ferromagnetic due to work hardening”.
In conclusion, if a piece of supposedly pure 10K or 14K or 18K gold jewelry is attracted to a strong magnet, and you have no reason to think there’s a good reason for it (ie a spring inside a clasp, or a surgical steel post on a gold earring, or the piece looks like it might be “blue white gold”), then beware. It is very probably not what it’s marked to be.
03-17-2012 04:09 PM
Will do, but I had hoped to hear if anyone else had run across gold that they felt was truly what it was marked...and yet was attracted to a strong magnet (such as a rare earth magnet).
03-20-2012 05:47 PM
The same procedure used for platinum should be used for 18K white gold. The material on the stone should start changing to a light bronze color in about three minutes. For 14K white gold, the material on the stone should disappear in 15 seconds. Lots of buyers test white gold using the same as they do for yellow gold and get a negative. Here's a good guide: http://www.esslinger.com/testinggoldsilverandpreci
03-20-2012 05:52 PM
Here's another good post that's here on Ebay. http://reviews.ebay.com/Testing-Lightly-Magnetic-W
05-26-2012 04:17 PM
Hello there speculators and non- belivers !!!
YYYYEEEESSSSS !!!! there is 14k gold with high iron content.
They are rare yellow gold iron blends and they are antique in our expirience. You cant fool a spectrometer.:-p
01-20-2013 11:37 AM
Yes I have run across this many times mostly in earrings that are marked and tested with acid to be true 14k or 10k but being magnetic I do not take a chance I feel as I am passing up something good but can not be sure I would like to find out if it is true that some gold sticks to a magnet
03-25-2013 07:08 PM
I have an 18k gold watch and watch band that has been tested and is gold, the band is also slightly magnetic. So, I do not think saying gold can not be magnetic is really a true statement.
04-09-2013 08:22 AM
ha ha, everything is "special" "hot" "new" "rare".....uhmmm yup really!
as if 10k gold filled is some rare species. "hey look, 10k gf/ep/solid/" It's "gold filled, and electroplated and filled"....he he he , INDEED it must be special.
does anyone even know what that means? it means NOTHING. It means it's crap.