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 Post subject: acid tested gold can black. help .
PostPosted: Wed Mar 14, 2012 10:42 pm 
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hello, sorry to bother everyone with a complete novice question but I wonder if any one can help?
i know nothing about jewellery except what 9ct etc..means.
i bought a lovely filligre bracelet off ebay about 13 grams in weight
it is marked in 2 places as 14k gold
i noticed that the clasp which has a 14k hallmark on is magnetic ,though the rest of the bracelet is not .
i bought a acid testing kit and put a bit on the magnetic clasp and found that the gold I tested turned black
is it meant to do that? it looks awfull.
i also put some solution on the fine filligre part and the gold has gone a darkish brown colour plus acid has eaten through gold and 1 fine link has come away from clasp .
my bracelet looks awfull with the black and brown colouring.
do you think bracelet is gold or not?
1 clasp marked 14k is magnetic ans other clasp end also marked 14k and main bracelet is not magnetic...
I have ruined my bracelet and also have loads of yellow marks on my hand where I got acid on me..
thankyou for any advice.


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 Post subject: Re: acid tested gold can black. help .
PostPosted: Wed Mar 14, 2012 11:07 pm 
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Here is a tutorial on how I usually do gold testing



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 Post subject: Re: acid tested gold can black. help .
PostPosted: Wed Mar 14, 2012 11:56 pm 
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The local precious metal dealer in my area told me that some bracelets, necklaces etc..., that are real gold may have clasps with a higher content of lead which make them magnetic. This is done to make the clasps more durable.

If you don't return your bracelet because you like it so much, you might check with your jeweler about having it plated to make it look gold again.

Peach


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 Post subject: Re: acid tested gold can black. help .
PostPosted: Thu Mar 15, 2012 2:25 am 
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Um... lead isn't (ferro) magnetic. In fact, lead is diamagnetic, which means it would have a very slight tendency to repel any magnet.


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 Post subject: Re: acid tested gold can black. help .
PostPosted: Thu Mar 15, 2012 4:15 am 
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peraphs he would mean Nickel..... :roll: :roll:
ciao
albé

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 Post subject: Re: acid tested gold can black. help .
PostPosted: Thu Mar 15, 2012 12:23 pm 
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The establishment I'm referring to has been there a long time, however, I did get the information from the son (family business). I will have a chat with the owner (dad). Thanks for the info!!!

Peach


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 Post subject: Re: acid tested gold can black. help .
PostPosted: Thu Mar 15, 2012 12:56 pm 
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thanks guys , i just found something on google where someone says that the clasp maybe could have a metal spring inside clasp which is making it magnetic..
do you think that could be right
though none of my other clasps react to magnet


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 Post subject: Re: acid tested gold can black. help .
PostPosted: Thu Mar 15, 2012 10:01 pm 
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You might check the internet for a "findings" manufacturer and contact the company to find out if certain clasps utilize the type of spring you mentioned and what type of metal is usually utilized in this mechanism.

Good Luck!
Peach


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 Post subject: Re: acid tested gold can black. help .
PostPosted: Thu Mar 15, 2012 10:35 pm 
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winterwhite11 wrote:
thanks guys , i just found something on google where someone says that the clasp maybe could have a metal spring inside clasp which is making it magnetic..
do you think that could be right
though none of my other clasps react to magnet

The type of clasp that uses a steel spring is called a Spring Ring, images here: http://www.google.com/search?q=spring+ring+clasp&hl=en&client=firefox-a&hs=6bi&rls=org.mozilla:en-US:official&channel=s&prmd=imvns&tbm=isch&tbo=u&source=univ&sa=X&ei=CqRiT4TzO6vXiALE7Z3MCA&ved=0CEsQsAQ&biw=960&bih=630

It's possible for other clasps contain magnetic metals but this is the most common type.

In most cases if "gold" is magnetic it's either gold plate or gold filled over a magnetic base metal.

In your first post you neglected to say what type and strength of acid you used in your tests. When acid is applied directly to 10K or lower a brownish hue is often seen on the metal. The fact that some of your bracelet metal was entirely dissolved indicates to me you used either too strong an acid mixture like aqua regia or that the item is not gold. Did you observe any greenish foam? That would indicate plating over base metal.

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