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How To Test Jade If Its Real
- serpentine ("New Jade" or "Olive Jade")
- aventurine quartz
- grossular garnet ("Transvaal jade")
- Chrysoprase ("Australian jade" - most of it comes from Queensland, Australia)
- Malaysia Jade (permanently dyed translucent quartz that may be called by its color – Red Jade, Yellow Jade, Blue Jade)
- opaque dolomite marble ("Mountain Jade" - from Asia, dyed in vibrant colors)
If you see anything resembling layers with the 10X loupe, you're probably looking at jadeite that's been "doubled" or even "tripled" (thin layer of gem-quality jadeite sometimes glued over a different base).
- Observe the density. Both jadeite and nephrite have a very high density (jadeite - 3.3; nephrite - 2.95). Density is measured by dividing the weight (in grams) by the volume (c.c.).
- A specific density gravity test can be performed as described below, or you can judge the density less accurately by tossing the stone in the air and catching it in your palm. If it feels heavier than most stone pieces of the same size, it is more likely to be authentic jade.
- Another way to judge density is to observe the sound of plastic beads gently tapping each other. If you have a piece of real jade, clink it against the stone in question. If it sounds like plastic beads, then the stone in question is probably fake.
- Wind a strand of hair around the piece. then hold it over an open flame, such as a match or a lighter, for about a second. If the hair burns away, the piece is not real. But if it stays intact, the piece should be real.
- Perform a scratch test. Jadeite is very hard; it will scratch glass or even metal. Nephrite, however, can be much softer, so performing a scratch test improperly may damage a genuine piece. Use the blunt end of a pair of scissors and gently press down and draw a line on an area on the jade piece that is not visible (bottom or end of the piece). Avoid any weathering surfaces because these are much softer and can be easily damaged. If the scratch makes a white line, gently wipe it off (it might be metal residue from the scissors). Is there still a scratch? If so, it's probably not authentic jade. If it scratches glass or steel, it could still be many of the alternatives to jade as well, including the various forms of green quartz and prehnite.
- Perform this test at your own risk. The piece may be very valuable, even if it's not made from jade, and can lose significant value if scratched.
- Look for other deceptive practices. Even if you have real jade in your hands, it can still be treated by dyeing, bleaching, use of stabilizing polymers, and creating jade doublets and triplets. Jade is divided into three categories based on these possibilities:
- Type A - natural, untreated, undergoes a traditional process (plum juice washing and polishing with beeswax), no "artificial treatments" (e.g. high temperature or high-pressure treatments), "true" color.
- Type B - Chemically bleached to remove impurities, injected with polymer with the use of a centrifuge to enhance translucency, covered with hard and clear plastic like coating, subject to instability and discoloration over time because polymer gets broken down by heat or household detergent, still 100% real jade with 100% natural color.
- Type C - chemically bleached, dyed to enhance color, subject to discoloration over time due to reaction with strong light, body heat or household detergent.
- Gather the Things You'll Need as outlined below.
- Use crocodile clamps to grasp the jade item. If the scale doesn't come with crocodile clamps, wrap the tested jade with a piece of string, a rubber band or a pony tail holder.
- Lift the spring scale by its top handle and write down the weight of the jade item in air. (Note this should be a scale based on grams and therefore measuring force in dynes - c.g.s system)
- Gently place the jade item completely into the water bucket and write down its weight in water. The clamp can touch the water; it shouldn't significantly affect the weight. If you're concerned, however, use one of the alternatives described above. Since the test is based on the difference in weight, as long as the string, band or pony tail holder remains on the jade both in the air and in the water, the difference will be the same.
- Calculate the volume of jade item: weight in air then divide by 1000 (or 981 if you have a calculator handy) minus weight in water divided by 1000 (or 981 if you have a calculator handy). This gives the mass in grams in air and the apparent mass in water. Subtract the in water value from the air value, this gives you the volume in cc.
- Calculate the density of the jade item: mass in air divided by volume. Jadeite has a density of 3.20-3.33 g/cc, while nephrite has a density of 2.98 - 3.33 g/cc.
- If you really love jade and want high quality pieces, the piece you purchase should be accompanied by a lab certificate verifying that the piece is "A" quality. Most established, high end retail jewelers only sell A quality.
- If there are air bubbles in the jade, it is not real.
- Ancient jade pieces are usually unique. If you see a dealer selling many designs that look similar, this is a red flag. Ask plenty of questions, and request a certificate of authenticity.
- With a scratch test, you can destroy a perfectly good piece of nephrite jade.
- Never do a scratch test on a piece you don't own. If you damage the piece, you will be forced to pay damages. Be sure to clean it with alcohol before you start.
Things You'll Need
For the density test:
- spring scale (100 gram, 500 gram, or 2500 gram, depending on the weight of the piece(s) you're testing)
- bucket, big enough for you to dip your piece(s) of jade in
- pony tail holder
- rubber bands
- paper towel (to dry items)
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