How to tell if jade is real

To tell if jade is real you have to answer two separate questions. Is the material jade at all, meaning jadeite or nephrite, and not glass, quartzite, serpentine or marble? And if it is jade, has it been bleached, filled with resin or dyed? Home checks can expose many imitations and some treated pieces. None of them can prove a piece is untreated, and for anything of real value only a gemological laboratory report settles it.

The two jades are different minerals with different numbers. GIA lists jadeite at a specific gravity of 3.34 and a Mohs hardness of 6.5 to 7, and nephrite at 2.95 and 6.0 to 6.5. The rest is in how jadeite and nephrite differ.

What each home test shows, and how it misleads

Test	What a result can show	What it cannot show, and what fools it
Price against appearance	A bright, translucent, evenly colored piece offered far below what that look normally costs is almost always treated or not jade. Dealers trust this before any instrument.	It only works as a warning. A high price proves nothing.
Color	Natural color is often uneven and fades gradually into the body. Perfectly uniform color, or color collected in a network of fine cracks, is a warning.	The color itself identifies nothing. Both jades occur in many colors.
Touch (cool feel)	Stone or plastic. Plastic feels warm because body heat quickly warms its surface.	Any stone feels cool, so touch cannot separate jade from quartzite, marble or serpentine, or treated from untreated.
Heft	Jadeite is denser than quartz and serpentine, so an imitation of the same size feels lighter beside a real piece.	The difference between treated and untreated jadeite is far too small to feel.
Sound (tap)	An untreated jadeite bangle hung from a thread rings clearly. A bleached, resin-filled one sounds dull.	Coarse-grained untreated jadeite sounds dull too. No use on pendants or small carvings, and unreliable for nephrite.
Scratch	A knife blade (about 5.5 on the Mohs scale) should not bite into either jade. If it does, the piece is a soft imitation such as marble or most serpentine.	It damages a real piece and clears a hard fake: quartz is 7, so dyed quartzite and aventurine pass. Dealers say to know this test and not use it.
Weight in water	Density: about 3.34 fits jadeite, about 2.95 nephrite, about 2.65 quartz or quartzite.	Treatment. A bleached, filled bangle can give a perfect jadeite figure.
10x loupe	A web of fine etched cracks and pits on the polish marks acid bleaching. Untreated jadeite is smooth, with at most a faint orange-peel dimpling.	A clean surface clears nothing. A specialist US jade dealer says even experts cannot be certain by eye.
Flashlight	How color is distributed, dye sitting between the grains, round gas bubbles in glass.	Strings of bubbles in glass can pass for natural structure.
UV lamp	Untreated jadeite usually shows no glow. Resin, wax and dye may fluoresce.	GIA says fluorescence alone cannot give a definitive identification. No glow is not a pass.

Sound is where the trade contradicts itself. For jadeite bangles dealers agree on the ring and on its limits. For nephrite, GIA notes that the stone rings musically when struck, yet in one dealer’s demonstration a white marble bangle rang brighter than the nephrite beside it, a second dealer could not separate nephrite from imitations by tapping, and a third finds marble and quartzite duller. Do not rely on sound for nephrite.

The order to check a piece: price against appearance first, then the loupe on the polished surface, a strong white light, weight in water, and last a 365 nm UV lamp in a dark room. The loupe, light and UV technique is in checking jade with a flashlight or UV light. Bangles have their own routine, including the tap test, in how to check a real jade bracelet. For an uncut rock, start with how to identify raw jade.

How to tell if jade is real with water

The one water test that holds up is hydrostatic weighing, which measures specific gravity. The method is the one in the Gemology Project’s guide to the hydrostatic balance. Weigh the piece dry. Weigh it again hanging fully submerged in water from a thin thread. Then:

specific gravity = weight in air ÷ (weight in air − weight in water)

Here is how the numbers work. This is arithmetic from the published densities, not a measurement of a real piece. A 60.00 g bangle that reads 42.04 g in water has lost 17.96 g, and 60.00 ÷ 17.96 = 3.34, the figure for jadeite. A reading of 39.66 g would give 2.95 (nephrite), and 37.36 g would give 2.65 (quartz).

The scale needs to read to 0.01 g. Air bubbles clinging to the stone or the thread skew the result, and a drop of detergent in the water reduces the error from surface tension.

A correct figure shows only that the material is consistent with jadeite or nephrite. It cannot detect treatment. GIA examined a bangle that measured a specific gravity of 3.34 and a refractive index of 1.66, exactly the values of untreated jadeite, and infrared testing showed it had been bleached and heavily impregnated. The folk versions, such as watching whether a drop of water beads on the surface, have no gemological basis.

What fake jade looks like

Fake jade often looks better than real jade at the same price. These are the usual materials and what tends to give each away:

Material	Often sold as	What gives it away
Glass	Jadeite or white nephrite	Round gas bubbles and no grain. Be suspicious of a cheap piece that is completely clean inside.
Quartzite, usually dyed	Jadeite or white nephrite	Glassy and granular, with a specific gravity of 2.65.
Aventurine quartz	“Indian jade”	Passes the knife test, but has quartz’s low density.
Serpentine	“Korean jade”	Most of it scratches with a knife. Specific gravity about 2.5 to 2.8.
Marble or dyed calcite	White nephrite, “Mexican jade”	Soft (calcite is 3 on the Mohs scale), often with parallel banding and a fine sugary sparkle.
Vesuvianite, hydrogrossular garnet, amazonite	“California jade”, “Transvaal jade”, “Amazon jade”	Trade names, not kinds of jade. Vesuvianite overlaps jadeite in density and hardness, so home tests can miss it.

In one of two glass bangles examined by GIA, strings of bubbles were visible without magnification and could easily have been taken for natural jadeite structure. New imitations also keep appearing: in 2025 GIA’s journal described a carved bottle submitted as jadeite that was a dolomite rock with green mica, and it took Raman spectroscopy and chemical analysis to identify it.

Real jade that has been treated

Much of what gets called fake jade is genuine jadeite that has been altered. The trade sorts it by letter: A jade is natural and finished only with wax, B jade has been bleached with acid and impregnated with polymer resin, and C jade is dyed. One trade estimate from a US jade wholesaler puts B jade at roughly 5% to 10% of the value of the equivalent untreated piece.

Two signs are within reach at home. Bleaching leaves the cobweb of etched cracks on the surface. Dye collects in veins, surface cracks and the gaps between grains, giving a net-like pattern under a loupe and strong light. A stone can be dyed in one area and naturally colored in another, so check the whole piece. Not finding these signs proves nothing: the GIA study that characterized B jade found infrared spectroscopy to be the only method that gave conclusive evidence of polymer in all cases. Dealers add that much of the cheapest treated material is not jadeite at all but quartzite and marble put through the same process. The letters are explained in type A, B and C jade.

Nephrite is checked differently

The A, B and C letters are not normally used for nephrite, although dealers describe dyed nephrite, long wax or oil soaking that hides cracks, and artificial colored skin applied to pebbles. Its usual stand-ins are marble, quartzite, serpentine and glass, and against those dealers look for nephrite’s soft, greasy to waxy luster. They do not rely on home tricks themselves: they send anything doubtful to a laboratory, because several stones look and feel almost identical to nephrite.

Certificates, and when to pay for a lab

A certificate that comes with a cheap piece proves little. Dealers document wholly fake certificates with their own fake lookup websites, and genuine certificates photocopied for a different stone. Enter the report number on the laboratory’s own website, found independently and not through a link or QR code printed on the paper.

Then read what the report says. It has to state treatment status, not just the species: a certificate reading only “jadeite” tells you nothing about bleaching, filling or dye. A GIA report quoted in a Sotheby’s catalogue shows adequate wording, stating that the jadeite jade “has no indications of impregnation”.

A laboratory can do what you cannot: infrared spectroscopy for polymer and wax, and Raman spectroscopy for the mineral itself. The test costs a small fraction of the price of a significant piece, and dealers across the trade give the same advice for anything expensive: have it tested at an independent laboratory of your own choosing, whatever paperwork it came with.

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