Place it in a glass of water. Real gold and platinum, classified as 'heavy metals' (i.e. metals denser than water), will sink straight to the bottom. If your ring rises to the surface, hovers around somewhere in the middle or even falters in its sinking process, it's definitely not solid gold or platinum.
A real diamond will reflect light easily, and provide you with a disco ball or rainbow-like display. You can use a flashlight or lamp to do this and it will work best with white light rather than yellow. If the stone absorbs the light, then there's a chance that it's a fake.
Many jewelers will appraise your stone free of charge and experts will often be able to tell immediately if your diamond is authentic or not. If your stone came with a certificate, your jeweler should be happy to take a look at it and tell you whether it is from a trustworthy source.
As straightforward as it sounds, fill a glass of water at home to roughly three-quarters full. Separate the stone so that it is loose, and drop it into the water. Diamonds are highly dense and a genuine gem will sink to the bottom – every time. If it hovers to the surface or only partially sinks, then it is a replica.
A sparkle test is quick and easy to do since all you need are your eyes. Simply hold your diamond under a normal lamp and observe the bright shimmers of light bouncing off the diamond. A real diamond provides an exceptional sparkle since it reflects white light extremely well.
Does this mean that diamonds have some iron or any other magnetic materials inside or the jewelers have ripped us of? A: Pure diamond is not magnetic. If you're lucky, your mum may have gotten a real diamond with some small magnetic impurities.
If the hallmark is absent, this could mean the jewelry does not contain real gold. However, there are other possible explanations. It is possible the hallmark has worn away over time, which can happen if the item is in constant contact with skin.
If you have a loose diamond to test, fill a regular glass about ¾ of the way full with water. Gently drop the diamond into the glass. If the diamond sinks to the bottom, it's real. If it floats at the surface or just underneath, it's likely a fake.
The way that diamonds reflect light is unique: the inside of a real diamond should sparkle gray and white while the outside should reflect a rainbow of colors onto other surfaces. A fake diamond, on the other hand, will have rainbow colors that you can see inside the diamond as well.
A fake diamond will have rainbow colors that you can see inside the diamond. “People have a misconception that diamonds sparkle like a rainbow, but they don't,” Hirsch said. “They do sparkle, but it's more of a gray color.
The Sparkle Test
Synthetic or fake stones, sparkle less than real, or mined diamonds. With light reflection, look for shades of gray. Synthetic stones, such as cubic zirconia, sparkle with more iridescent colors. Natural diamonds reflect light in more grayish hues.
Place your jewelry on a table or hold it in your hand, pour some white vinegar on the metal directly (a dropper can also be used) if the metal of the jewelry changes its color, it is not pure gold and if it keeps shining then you have real gold in your hand.
Hold a strong magnet on your piece of jewelry. If the magnet sticks, this is an immediate indication of a fake material being used. Most simulated gold and silver is made of brass, copper, or other base metals commonly known as “pot metal." These are not attracted to a magnet, so this test won't work on them.
Gold Isn't Magnetic
If that new “gold” ring is attracted to your most powerful kitchen magnet, it's not real gold. That's not to say that if your piece doesn't cling to the magnet, it's 100% real (silver and other metals also aren't magnetic). The magnet test is simply one way to test for gold content.
If you're holding a genuine diamond, you'll witness an intense blue color on the diamond surface. A fake gemstone will reveal itself through other colors — including green, yellow, or gray tints. The validity of this test is limited, though.
Take your diamond between two fingers and blow a puff of air into it. The moisture and heat from that air will fog up your stone. If this fog dissipates quickly, your diamond is real and if it takes a while to dissipate then you need to re-evaluate your jeweler. Diamonds conduct heat and disperse it quickly.
Nearly all real gold is stamped with a hallmark that notes the karat weight of the jewelry, like 10K or 14K. This stamp is usually found on the clasp of a necklace or bracelet, or on the inner band of a ring.
If you have a ring, or want to buy a ring that has no stamp, you can always have the ring tested. Jewelers can perform a quick acid test (acid testers sold here) on the metal to determine the actual content. Plus, you can always have the correct mark stamped back into the ring again.
By law, gold jewelry sold by a vendor must have a stamp of the piece's purity, so finding a stamp is a good sign! If you can't find a stamp, it's possible it wore off with time, or was sold before the law was passed. Don't worry if there is no stamp to be found, you can always consult an expert!
If it's real gold it will not stick to the magnet. (Fun fact: Real gold is not magnetic.) Fake gold, on the other hand, will stick to the magnet. If that necklace leaps to the magnet, your significant other has some explaining to do.
True diamonds have high density and should quickly sink to the bottom of the glass. Fake diamonds are not as thick, and therefore, more likely to float in water.
First off, if your "pure gold" is magnetic, then there is iron inside (or maybe nickel). In fact, this is one way to tell if jewelry is actually gold. If it's not attracted to a magnet then there is no iron - but it still might not be gold. Scammers have been known to coat lead, copper, and aluminum.