Color: Natural Variation vs. Uniformity

Real Turquoise: Natural turquoise exhibits a range of colors, from vibrant sky blue to bluish-green and even apple green. The color is often uneven, with variations and subtle shifts within the stone. This natural color zoning is a hallmark of genuine turquoise. Look for subtle differences in shade and saturation within the stone.

Fake Turquoise: Many imitations, especially those made from dyed howlite or plastic, display an unnaturally uniform and consistent color. The color may appear too perfect, too bright, or too evenly distributed throughout the stone. Be wary of turquoise that looks flawlessly colored without any natural variations.

Matrix: The Story in the Veins

Real Turquoise: The matrix is the network of veins or patterns running through the turquoise. In genuine turquoise, the matrix is naturally formed and random. It can be web-like, spiderweb, or blotchy, and the color of the matrix can vary from brown and black to golden or even shades of blue. The matrix is typically embedded within the stone, appearing three-dimensional.

Fake Turquoise: Imitations often have a matrix that is painted or drawn onto the surface. This painted matrix will often look flat, artificial, and sit on top of the stone rather than being integrated within it. The patterns may be repetitive or overly symmetrical, lacking the natural randomness of genuine matrix. Some fakes may even lack a matrix entirely, especially if they are trying to mimic certain types of turquoise.

Actionable Tip: Examine the matrix closely with a magnifying glass. Does it look like it's part of the stone, or painted on top? Are the patterns naturally irregular or suspiciously uniform?

Luster and Surface: Shine and Texture

Real Turquoise: Real turquoise typically has a waxy to slightly vitreous (glassy) luster. It shouldn't appear overly shiny or plastic-like. The surface can range from smooth to slightly porous, depending on the type and treatment of the turquoise. It should feel cool to the touch initially.

Fake Turquoise: Many imitations, particularly plastic or resin, will have a very glossy, plastic-like shine. They may feel warm to the touch immediately, unlike the coolness of stone. Some fakes might be coated with a resin or sealant to enhance their appearance, resulting in an unnatural, overly smooth, and often sticky surface.

Actionable Tip: Observe the luster in different lighting conditions. Real turquoise will have a subtle, natural sheen, not an artificial, high-gloss shine.

The Scratch Test: Unveiling Hardness

The Principle: Turquoise has a hardness of 5-6 on the Mohs Hardness Scale. This means it's softer than glass (5.5-6.5) and a steel knife blade (around 5.5-6.5). Many imitations, especially plastic and resin, are significantly softer.

The Test (Use Caution): In an inconspicuous area, gently try to scratch the turquoise with a fingernail (hardness ~2.5) and then with a copper penny (hardness ~3). Real turquoise should not be scratched by these materials. Then, very cautiously try to scratch it with a steel knife blade or the edge of a glass object (like a glass tile). Real turquoise might be slightly scratched by these, but it should resist significant scratching. Plastic or resin imitations will scratch much more easily with these tools.

Important Note: This test can be destructive and should be performed with extreme care, preferably in an area that is not visible when worn. Avoid scratching the main face of the stone. If you are unsure, skip this test.

The Water Absorption Test: Porosity Check

The Principle: Natural turquoise is porous to varying degrees. It can absorb a small amount of water. Many imitations are non-porous materials like plastic or heavily sealed stones.

The Test: Place a tiny drop of water on an inconspicuous, unpolished area of the turquoise. Observe what happens. Real turquoise will slowly absorb the water, causing the area to darken slightly. The water droplet may bead up slightly initially but should eventually seep in. Fake turquoise made of plastic or resin will not absorb water; the droplet will simply sit on the surface or roll off.

Important Note: Use only a tiny drop of water and observe carefully. Wipe away any excess water immediately after the observation. This test is more effective on untreated or lightly treated turquoise. Heavily stabilized or resin-treated turquoise may show reduced porosity.

The Acetone Test: Dye Detection

The Principle: Many fake turquoise stones are made from white stones like howlite or magnesite that are dyed blue to resemble turquoise. Acetone (nail polish remover) can sometimes dissolve or remove dyes.

The Test (Use Caution): Dab a cotton swab with acetone (nail polish remover). Gently rub the swab on an inconspicuous area of the turquoise, such as the back or an unpolished part. Examine the cotton swab. If the swab picks up blue or green color, it indicates the presence of dye, suggesting a fake. Real turquoise's color is inherent and will not rub off with acetone.

Important Note: Perform this test in a well-ventilated area. Acetone is flammable and should be handled with care. Test in an inconspicuous area to avoid any potential damage or discoloration. Some stabilized turquoise may also release a slight color due to surface treatments, so interpret results cautiously and consider other tests as well.

The Heat Test: Smell and Melt (Use Extreme Caution!)

The Principle: Plastic and resin imitations will react differently to heat than natural stone. They may melt, soften, or emit a plastic-like odor when heated.

The Test (EXTREME CAUTION REQUIRED, BEST AVOIDED UNLESS YOU ARE VERY EXPERIENCED AND DISPOSING OF THE STONE): This test is potentially destructive and should only be attempted with extreme caution and ideally on a piece you are willing to potentially damage. Use a heated needle or pin (heated over a flame or with a soldering iron – carefully!). Very briefly touch the hot needle to an inconspicuous area of the turquoise. Observe the reaction and smell. Plastic or resin will melt, soften, or emit a distinct plastic or chemical odor. Real turquoise will be unaffected by this brief exposure to heat and will not emit a plastic smell.

Important Note: This test carries a risk of damaging the stone and should be considered a last resort, and preferably avoided by inexperienced individuals. If you are unsure, do not perform this test. Inhaling fumes from burning plastic is harmful. Perform in a well-ventilated area if you proceed with extreme caution.

Magnification: Revealing Microscopic Details

The Principle: Examining turquoise under magnification (10x loupe or microscope) can reveal details not visible to the naked eye, helping to differentiate natural materials from synthetics or imitations.

What to Look For:

• Natural Inclusions: Real turquoise often contains microscopic inclusions, natural imperfections, and variations in texture. These are signs of natural formation.
• Dye Concentration: Under magnification, dyed imitations may show concentrations of dye in cracks or crevices, or an unnatural, pixelated appearance of color.
• Plastic or Resin Texture: Plastic and resin imitations may exhibit a smooth, uniform, and sometimes bubbly texture under magnification, lacking the natural irregularities of stone.
• Matrix Appearance: Magnification can further help assess if the matrix is painted on the surface or genuinely embedded within the stone.

Actionable Tip: Invest in a 10x jeweler's loupe. Practice examining known real and fake turquoise samples under magnification to train your eye.

Howlite and Magnesite: Dyed White Stones

Howlite and magnesite are white minerals that are porous and readily accept dyes. They are frequently dyed blue to mimic turquoise. These are perhaps the most common turquoise imitations.

How to Identify:

• Unnatural Uniform Color: Dyed howlite often has an overly uniform, bright blue color that lacks the subtle variations of natural turquoise.
• Painted Matrix: The matrix is often painted on and looks flat and artificial.
• Chalky Texture: Howlite and magnesite can have a slightly chalky or porous texture, especially in less polished areas.
• Acetone Test: As mentioned earlier, the acetone test is often effective in detecting dyes on howlite and magnesite.

Plastic and Resin: Synthetic Substitutes

Plastic and resin are inexpensive and easily molded materials used to create convincing-looking turquoise imitations.

How to Identify:

• Lightweight: Plastic and resin are significantly lighter than stone. Real turquoise will feel substantial for its size.
• Warm to the Touch: Plastic and resin feel warm to the touch almost immediately, while stone remains cool for a longer time.
• Plastic Luster: The shine is often very glossy and plastic-like, lacking the waxy luster of real turquoise.
• Heat Test (Cautiously): Plastic and resin will melt or smell like burning plastic when heated (use extreme caution).

Reconstituted Turquoise: Dust and Glue

Reconstituted turquoise is made from fragments and dust of real turquoise that are mixed with a binder (often resin or plastic) and compressed into a solid form. While it contains some real turquoise, it's significantly less valuable than solid, natural turquoise.

How to Identify:

• Uniform Appearance: Reconstituted turquoise often has a very uniform color and texture, lacking the natural variations of solid turquoise.
• Grainy or Speckled Texture: Close inspection may reveal a grainy or speckled texture, indicating it's made of small particles bonded together.
• Resin Odor (Sometimes): In some cases, a slight resin or glue odor might be detectable, especially when heated gently (use caution).
• Lower Price: Reconstituted turquoise should be priced significantly lower than solid natural turquoise. If the price seems too good to be true, it might be reconstituted.