Jade is a beautiful green, orange or white colored stone, the quality of which can be classified as low, medium or high level. If you want to buy a jade item or you already own one, it is interesting to know if it is genuine stone or a fake. To learn how to recognize real jade and perform some simple tests, read on.
Steps
Part 1 of 3: Recognizing the Jade
Step 1. Familiarize yourself with real jade
Only jadeite and nephrite are considered genuine jades.
- The most expensive and popular jadeites (Burmese Jadeite, Burmese Jade, Imperial Jade or Chinese Jade) are generally mined in Myanmar (formerly Burma), but small quantities are also found in Guatemala, Mexico and Russia.
- 75% of the world's jade comes from British Columbia's nephrite quarries, but is also mined in Taiwan, the United States and, in small quantities, Australia.
Step 2. Familiarize yourself with imitations
The materials that are passed off as jade can be:
- Serpentine (also called "New Jade" or "Olive Jade")
- Prehnite
- Adventurine quartz
- Tsavorite ("Jade of the transvaal")
- Chrysoprase ("Australian jade" - most of it is mined in Queensland)
- Malaysian jade (permanently colored translucent quartz, which is named according to the color red jade, yellow jade, blue jade)
- Matt dolomitic marble ("Mountain Jade" - comes from Asia and is colored with bright colors)
- In New Zealand, the Greenstone or "Pounamu" is very popular with the Maori. The Maori recognize four main types of pounamu, identifying their color and translucency: kawakawa, kahurangi, īnanga. These are nephrites. They also appreciate a fourth type of pounamu - "tangiwai" - from Milford Sound, which, although of great value, is actually bowenite.
Step 3. Look at the stone against a light source
If you can, examine the internal structure with a 10x magnifying glass. If you can see fibrous or granular interconnections, similar to felt or asbestos, it is likely genuine nephrite or jadeite. Chrysoprase, on the other hand, is microcrystalline, so it will appear homogeneous.
If you see something that looks like layers, you are probably looking at layers of jadeite glued to a less valuable base
Step 4. Look for other deceptive practices
Even if you have real jade in hand, it may still have been treated with dyes, whiteners, stabilizing polymers, or created with overlapping layers. Jade is divided into three categories based on these aspects:
- Type A - Natural, untreated, undergoes a traditional process (washing with prune juice and polishing with beeswax), no artificial process (high temperature or high pressure treatments). It has a true color.
- Type B - Chemically bleached to remove impurities; Polymers are injected through a centrifuge to improve transparency, and it is covered with a hard, transparent, plastic-like coating. It is subject to instability and discoloration over time because polymers break down with heat or with household detergents; however, it is 100% pure jade with a completely natural color.
- Type C - Chemically bleached; artificially colored to improve its appearance; it is prone to discoloration over time due to reaction to strong lights, body heat or household cleaners.
Part 2 of 3: Taking the Basic Tests
Step 1. Throw the stone into the air and catch it with your palm
If it looks heavier than most stones of the same size and has passed the magnifying glass test, it is probably real jade.
This is obviously an inaccurate, albeit effective, analysis that was done in the past by merchants and buyers of gems
Step 2. Another way to assess density is to consider the sound of two stones touching
If you have a piece of real jade, knock it against the stone in question. If it sounds like a plastic bead, the stone is probably fake. If you hear a deeper, more resonant sound, it could be genuine jade.
Step 3. Hold the jade in your hand
It should be cool, smooth, and soap-like to the touch. If it is genuine jade it takes some time to heat up. This is very subjective, and is more useful if you can compare it to real jade of a similar size and shape.
Step 4. Run a scratch test
Jadeite is very hard; it will scratch the glass and metal. However, nephritis is much softer, so doing a scratch test incorrectly could damage an authentic piece. If the stone scratches glass or steel, it may still be one of the alternatives to jade, such as green quartz or prehnite.
- Use the blunt end of a pair of scissors and press gently on the non-visible part of the stone to avoid damaging it by drawing a line.
- Avoid sloped surfaces as they are much softer and can be easily damaged. If the scratch leaves a white line, gently remove it (this could be a metallic residue from the scissors). Is the scratch still present? If so, the stone is probably not authentic.
Part 3 of 3: Density Test
Step 1. Divide the weight by the volume of the object
Both jadeite and nephrite have a very high density (jadeite 3, 3 g / cc and nephrite 2, 95 g / cc). Density is measured by dividing the weight expressed in grams by the volume expressed in cubic centimeters.
Step 2. Use alligator clips to pick up the stone
If the scale does not contain such pliers, wrap the jade with a piece of string, a rubber band, or a hair tie.
Step 3. Lift the scale by its top handle and note the weight of the jade suspended in the air
It is better to use a scale that is calibrated in grams and not in dynes.
Step 4. Gently put the jade into the bucket of water and note its weight in the water
The gripper can touch the water; it should not alter the measurement significantly.
If this worries you, use one of the alternative methods of holding the stone. Since the test is based on the difference in weight, if you use the same object to hold the jade in the air and in the water, the difference will remain the same
Step 5. Calculate the volume of the object
Divide the weight measured in air by 1000 and from this value subtract the weight measured in water (always divided by 1000). In this way you get the mass expressed in grams in air and the apparent mass in water. The subtraction will give you the volume of the object expressed in cubic centimeters.
Step 6. Calculate the density of the jade:
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.
Advice
- If you value jade a lot and want a high quality piece, you should only purchase lab tested stones with a certificate that their quality is "A" type. Top-tier jewelers only sell A-quality stones.
- If you see air bubbles in the jade, it's a fake.
Warnings
- With a scratch test, you can ruin an authentic piece of nephrite.
- Never perform a scratch test on a part that isn't yours. You would be liable for damages. Make sure you clean it with alcohol before starting.
- Antique jade pieces are usually unique. If you see a retailer offering many similarly designed stones, be wary. Ask a lot of questions and ask for a certificate of authenticity.
