Real gold also doesn’t rust or tarnish when wet, so if you see a discoloration, you probably have plated gold.
You can also submerge the gold in a glass container with vinegar for 15 minutes. This is a slightly riskier method because vinegar might damage semi-precious stones on gold jewelry.
For example, a silver coloring might indicate silver or titanium. A red coloring could mean copper or brass.
Keep in mind that most gold items are blends of gold and other metals. Even something like a 14K piece of jewelry, 58. 3% gold, can leave these marks. Use other tests as well to ensure your gold is authentic.
Regular kitchen magnets might not be strong enough. For better accuracy, buy a powerful neodymium magnet from a home improvement store. The magnet test isn’t foolproof, since counterfeit gold can be made with non-magnetic metal like stainless steel. Also, some genuine gold items are made with magnetic metals such as iron.
Try getting an unglazed ceramic tile or a plate online or from your local home improvement store. This test scratches the gold a little bit but doesn’t typically leave much noticeable damage. It is much safer than other tests involving scratches or acid. Another way to do this is by spreading some cosmetic foundation on your skin and dragging the gold across it after it dries. Fake gold usually reacts with the foundation, leaving a green or black streak in it.
Use a magnifying glass to help you identify the hallmark. It can be tough to make out by eye, especially on smaller pieces of gold such as rings. Older pieces of jewelry may not have visible hallmarks. Sometimes the hallmark wears off over time, while in other cases the jewelry never got a stamp. Hallmarking became common in the 1950s in some areas, but in India for instance, it only became mandatory in the year 2000. [8] X Research source
The number rating system is easier to read than the karat rating system. For example, a rating of 375 means your item consists of 37. 5% gold. What number means gold depends on the country you are in. In the U. S. , for example, anything 9K and under is not considered to be gold, even though a 9K bracelet consists of 37. 5% gold. Counterfeit pieces may have markings making them look authentic, so don’t go solely on the hallmark unless you’re certain you are holding gold.
GP stands for gold plated, GF means gold filled, and GEP means gold electroplate. The markings vary a little depending on where the gold is from. For instance, gold from India contains a small triangle symbol indicating the government council responsible for the rating system. It then has a number rating and a letter code, such as K, for the jeweler.
You need the weight in grams to use in a calculation later. If the weight is in ounces, you won’t get an accurate result.
Vials with frequent millimeter markings on the side are useful for getting a more accurate measurement during the test. The amount of water you use doesn’t matter that much as long as you leave plenty of space for the gold. If you fill the vial to the top, dropping the gold into it causes the water to spill.
Keep in mind that it doesn’t matter if your vial is marked in milliliters or cubic centimeters. They are the same measurement, so either unit can be used in the test.
Write the second measurement down on a piece of paper. Note that this is the second measurement, not the initial one.
For example, if you started with 17 mL (0. 57 fl oz) of water that rose to 18 mL (0. 61 fl oz), that leaves a 1 mL (0. 034 fl oz) difference.
For instance, you have a gold item that weighs 38 g (1. 3 oz) and displaces 2 mL (0. 068 fl oz) of water. Divide 38 by 2 to get 19 g/mL, which is very close to the density of gold. The standard density differs a little depending on the type of gold you have. For 14k yellow gold, it’s about 12. 9 to 13. 6 g/mL. For 14K white gold, it’s around 14 g/mL. A piece of 18K yellow gold has an average density from 15. 2 to 15. 9 g/mL. A piece of 18K white gold has a density from 14. 7 to 16. 9 g/mL. Any 22K piece of gold has a density around 17. 7 to 17. 8 g/mL.
Testing kits are available online. Also, check with local jewelry stores. Most jewelers use this test for its accuracy.
Nitric acid tests require you to scratch your piece of gold. If the gold has personal value to you or you plan on keeping it, take it to a professional jeweler instead of doing the test yourself.
Regular gold does not react to the acid, so your item might be gold plated or a low-purity blend of metals. A milk-colored reaction usually indicates gold-plated sterling silver. If the acid turns gold, you have gold-plated brass.
The acids all increase in strength, so the acid used for 22K is stronger than the 12K one. If the 18K acid dissolves the gold but the 14K one doesn’t, you know your item is probably around 14K.
