Testing gold.

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Easylife
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Another toy winged it's way to me this morning - a gold and silver testing kit!
https://www.ebay.co.uk/itm/Practical-Go ... 635-2958-0
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I tend to find one or two gold items a year detecting inland but not all are hallmarked with their purity though you can often make a fair guess by their colour tone. Likewise about a dozen or more silver items usually show too but even if no hallmark you just know it's silver by it's look. But a while ago I found a gold looking bracelet with a foreign stamp so thought that it would be good to find out for sure if it is actually gold and it's purity? It looks about 18 karat to me but I'm no expert.
So let's find out.
First make a gold streak on the lydian stone.
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Next a drop of 10k acid, if it dissolves the streak then it's either 9k or not gold.
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Okay, no change so we're in. :thumbsup:
Now for a drop of 14k acid, still no change, so it's looking on track. :D
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I should have made the streak longer so I added another and tried a drop of 18k acid. Still no change so I expect it will be 20 karat?
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Now for a drop of 22k acid and it kind of disolved the gold. I think I'll do the 22k test again as there wasn't too much of a gold streak there. Yep, it has disolved the gold.
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So 20 karat gold it is, making a scrap value of about £380, enough to buy another toy! :Party:
D2 - 13"x11" coil - audio only.
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Easylife
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Now kiddies don't try this test without adult supervision. You don't really want to get any of the nitric and hydrochloric acid on you or anything else! :D :thumbsup:
D2 - 13"x11" coil - audio only.
Pete E
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That's an interesting kit, particularly the silver tester...I presume the neutraliser is to clean up the block after you finish?
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Pete E wrote: Thu Oct 28, 2021 4:58 pm That's an interesting kit, particularly the silver tester...I presume the neutraliser is to clean up the block after you finish?
You can test the purity of silver by the colour it goes. The neutraliser is just to neutralise the acid used but baking soda does the same job.
D2 - 13"x11" coil - audio only.
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Leeloo
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If you search YouTube there are a few on ‘Specific Gravity Testing’ it’s a handy way to test gold and surprisingly accurate
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Leeloo wrote: Sat Oct 30, 2021 8:36 am If you search YouTube there are a few on ‘Specific Gravity Testing’ it’s a handy way to test gold and surprisingly accurate
It is, I've used it to help determine other metal alloys though often not so clear cut on them as gold being the heaviest metal. This bangle is of folded construction so any void would sway the metal displacement volume but would still no doubt give a sure result. I just fancied having a testing kit to determine the purity. :thumbsup:
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Pete E
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With regards theses gold test kits, what happens if the item is actually just plated?
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Pete E wrote: Sun Oct 31, 2021 12:39 pm With regards theses gold test kits, what happens if the item is actually just plated?
You would need to file a little bit in an unnoticeable place to see if the item was just plated. With this item there was a small scuff on an edge showing the metal to be of consistent colour which was very reassuring for it to be gold. The kit would identify the purity of gold plating though. Though an SG test would also easily identify if an item was only gold plated. :thumbsup:
D2 - 13"x11" coil - audio only.
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