Whenever I sit down with someone to buy their gold, I always get a lot of interest and a lot of questions about how we test the gold to determine its purity and if it fact its really gold, gold filled or gold plated.
Some people also wonder how they can test their gold before they bring it to a gold buyer so that they are educated and so they know what they have and thus avoid, being taken advantage of, not to mention being prepared helps the appointment go a lot faster.
1. Checking Stamps and sorting Gold into Karats
The first thing you should do with a pile of gold your going to sell, is to sort it out into Karats. A karat is a measure of golds purity, not to be confused with Carat which is a unit used to measure stone weight, like diamonds. Since pure gold is too soft to use in Jewelry design, it is usually mixed with an alloy.
The most common grades of gold, in addition to pure 24K, are 22K (92%), 18K (75%), 14K (58%), 10k (41%) and 9K (38%).[
By law, gold sold in most countries must be stamped with the carat and the mark of the maker of the item. However it is common to see some pieces without stamps or stamps that are worn off. Have a pile for the items where you there is no stamp or you cant read it clearly. The stamps should be on the inside of the band on rings, on the clasp or loop for pendants and chains.
2. Magnetic Test
You will need a rare earth magnet to do this step. If you do not have one that is o.k, the gold buyer will go over your items for you.
If you are interested in seeing if something you have is really gold or silver before you go to an appointment with a gold buyer then pick up a magnet. They are available at gem supply shops and some industry places. There is a place in Sherwood Park called Terrick Enterprises that sells very powerful rare earth magnets that I use.
All Precious metals are Non-Magnetic so, run the magnet over the item, if it sticks then the item is not gold or gold plated over a magnetic alloy. Be careful, though and don’t throw out that gold chain if the clasp sticks to the magnet. Most clasps on gold chains have a steel pin inside of them, the main body of the chain however should not be magnetic.
3. Acid testing to determine Karat
First, I do not recomend doing this at home because working with Nitric acid can be dangerous and is at your own risk. When you sell your gold, the gold buyer will acid test your items to verify the karat stamped on the item.
The item is lightly rubbed on a test stone which removes a tiny little sample of gold. The test does not harm the item, and in most cases does not leave a mark and removes an insignificant amount of gold weight.
Acid is then put on stone over the mark left by the item . If an item is stamped 10K, we start with 10K acid and if the acid does not make the mark disappear then the item is 10K,
if the mark still appears crystal clear, then it might be better then 10K. We then use 14K acid to see if that makes the mark disappear, and then so on up through the acids until we find the one that makes it disappear.
The item is likely the karat of the acid below the one that disappeared the mark.
That is all! That is how gold is tested by a gold buyer to determine purity and authenticity. If you are considering selling your gold, give me a call at 780-628-6895. I would be happy to explain to you in person the testing process every step of the way.