Magnetic Jewelry Clasp

All that sparkles isn't gold. That's true enough but probably not good enough if you are going to understand the true value of your gold. Understanding some of the fundamentals about hallmarking and the tests commonly applied when valuing gold is useful; especially if you wish to sell gold either online or through a retail outlet.

Gold is normally hallmarked i.e. stamped to indicate the type of gold. For example, gold which contains 375 parts of gold per thousand is 37.5% pure and categorised as 9K Gold. Likewise, 14 Karat gold is 58.5% pure (585 parts per thousand) and 18k gold is 75% pure. Jewellers in the UK are not allowed to describe an item as solid gold unless it is hallmarked. UK hallmarks are 375, 585, 750, 916, and 999. The UK is also a signatory to the international convention on hallmarks which means convention hallmarks are also recognised in the UK. You can get more information at the British Hallmarking Council website.

The colour of gold has nothing to do with the quality and is the result of mixing the gold with different types of metals. Adding copper to the gold produces the rose coloured gold and Rhodium is used in Jewellery to produce the white gold colour. Given the use of hallmarking in the UK, the best starting point in checking the value of your gold is to examine it under a magnifying glass to check for the hallmark: either a UK hallmark or one that is recognised under the convention agreement. If there is no clear hallmark, then using a magnet to test for any magnetism in the metal which will at least show if it isn't gold. Precious metals are NOT magnetic. However, a lot of jewellery is made up of other metals parts today. For instance, clasps, springs and supports are often made of metal and will be magnetic and therefore care should be taken with this approach.

If you take or send your gold to a jeweller, they will first verify any hallmark. If this is not conclusive then they will test by filing an area of jewellery that is hidden and applying acid to see a change in the colour which will determine the Karat of the gold. The jewellery has to be filed to make sure that you are testing the gold and not just any surface plating.

According to historical accounts, the expression, 'the acid test', comes from the fact that acid testing has long been used for gold. You can buy acid testing kits to do this. This process involves you scratching the gold on a stone supplied and then testing the residue with acid. The time the gold remains following the application of the acid indicates the quality of the gold. If it lasts more than 30 seconds, then it is likely to be 18k or higher. Tests for higher quality gold often require comparison of the dissolve times of a known sample with the test sample.

Whilst this gives you some knowledge and understanding of gold valuation, ideally you should take your gold to a reputable jeweller to get a correct assessment of the quality and value before you sell gold