What is amethyst? “A purple variety of quartz”. (I’m sure most people know that.) But have you ever heard of green amethyst? Does that suddenly confuse you? After all, Wikipedia defines amethyst as strictly purple. So why does “green amethyst” exist? Curious? Let’s unravel its mysteries by exploring its characteristics, formation, and more!
Table Of Contents:
- What is Green Amethyst?
- Green Amethyst Color
- Green Amethyst Formation
- Green Amethyst Physical & Chemical Properties
- Green Amethyst Primary Sources
- Green Amethyst Symbolism & Energy
- Green Amethyst Buying Guide
- How to Differentiate Natural Prasiolite from Treated Green Amethyst？
- Green Amethyst Daily Cleaning & Care Tips
- Related FAQs
What is Green Amethyst?
Strictly speaking, “Green Amethyst” should be called “Prasiolite”. Prasiolite is a rare green variety of quartz. But why do so many people still call it “Green Amethyst”? Is this term correct? The answer is “Yes”. Why? It all comes down to its formation – naturally occurring Prasiolite is extremely rare. Most Prasiolite on the market is actually produced by heat treating or irradiating amethyst. This is why it is commonly referred to as green amethyst to correlate it with its source.
Green Amethyst Color
Artificially treated green amethyst ranges from pale mint green to deep olive green, with a transparent to semitransparent appearance. Natural Prasiolite typically has a soft light green with yellowish and grayish tones and is semitransparent.
Green Amethyst Formation
- Natural Formation: In very rare cases, amethyst undergoes natural radiation exposure or geological heating, causing changes in the oxidation state of iron and turning its color from purple to green – forming Prasiolite.
- Artificial Treatment: Most green amethyst available in the market is produced by heating amethyst to approximately 500°C. This process is stable and widely accepted in the gemstone industry. (This type of Prasiolite is often referred to as green amethyst.)
Physical & Chemical Properties of Green Amethyst
- Composition: Silicon dioxide (SiO₂), part of the quartz family alongside amethyst and citrine.
- Hardness: Mohs scale of 7, making it suitable for daily wear.
- Refractive Index: 1.544–1.553 (single refraction).
- Color Stability: Prolonged exposure to strong sunlight may cause fading, so it is advisable to avoid excessive sun exposure.
Green Amethyst Primary Sources
- Brazil: Is the largest global source of amethyst, the primary origin of heat-treated green quartz and some natural Prasiolite.
- USA, Canada, Poland: Small quantities of natural Prasiolite can be found.
- Africa: Some mining areas produce untreated, light green amethyst.
Symbolism & Energy of Green Amethyst
- Energy Properties: In spiritual practices, green amethyst is regarded as a “heart-healing stone”, symbolizing balance and renewal.
- Emotional Healing: Helps alleviate anxiety and promotes inner peace.
- Energy Cleansing: Linked to the heart chakra, aiding in releasing negativity.
- Creativity Boost: Inspires creativity and enhances concentration.
- Feng Shui Uses: Often placed in the east or southeast areas of a home to attract health and prosperity.
Green Amethyst Buying Guide
When selecting green amethyst, you can refer to the 4Cs criteria and follow these standards to choose a high-value gemstone:
- Color: The more intense and evenly distributed the green color, the higher the value of the green amethyst.
- Clarity: Stones without visible inclusions are more precious.
- Cut: A well-executed cut enhances the brilliance and sparkle of green amethyst.
- Carat Weight: Larger green amethyst stones are rarer and generally more expensive.
How to Differentiate Natural Prasiolite from Treated Green Amethyst？
Wondering how to tell the difference between natural Prasiolite and artificially treated green amethyst? Below are detailed methods for identification, including visual inspection and professional testing:
1. Color Observation
Natural Prasiolite usually exhibits a soft pale green hue with yellow or grayish tones. Highly saturated green shades are extremely rare. Its color distribution is naturally uneven, often displaying gradual transitions or color zoning.
Treated Green Amethyst typically has a bright, evenly distributed green color, often leaning towards cool-toned mint green or bluish-green. It rarely shows color zoning or gradients.
2. Microscopic Examination of Inclusions and Internal Features
Natural Prasiolite common inclusions include two-phase (gas-liquid) inclusions, needle-like rutile, or hematite crystals. It may also show natural growth lines (parallel striations or hexagonal crystal structures) and occasionally natural healing fractures with feather-like or cloudy edges.
Treated Green Amethyst may retain the original amethyst color banding. “Fried egg”-like white cracks around inclusions (caused by heat-induced fractures). Poorly treated stones may show surface burn marks or color concentration zones.
3. Professional Instrument Testing
- UV Fluorescence Response:
- Natural Prasiolite typically shows no fluorescence under long-wave UV light, with rare cases exhibiting weak yellow-green fluorescence.
Treated Green Amethyst may show weak red fluorescence or remain inert under short-wave UV light due to heat treatment residues. - Spectroscope Absorption Spectrum:
- Natural Prasiolite displays a faint iron (Fe³⁺) absorption band around 550 nm.
Treated Green Amethyst may lack natural spectral features or show a 653 nm absorption line similar to amethyst (indicating incomplete heat treatment). - Polarized Light Microscope Examination:
- Natural Prasiolite exhibits the typical hexagonal columnar growth structure of quartz, with interference colors matching standard quartz patterns.
Treated Green Amethyst may retain amethyst’s Brazil twin structure (alternating color bands), but the color has changed due to heat treatment.
4. Certification Identification
This is the easiest and most reliable method. Check the gemological certificate issued by the authority (e.g. GIA, AGL), these certificates will clearly state the origin of the color:
- Natural Prasiolite: “Color is natural“.
- Heat-treated Green Amethyst: “Color is due to heat treatment“.
5. Simple Test Method (Use with Caution)
Low-Temperature Fading Test: Place the gemstone in a -20°C environment (e.g., a household freezer) for several hours:
- Treated Green Amethyst: May temporarily revert to purple (reversible iron valence change).
- Natural Prasiolite: Remains color-stable and unchanged.
Warning: This method may damage the gemstone, so use it with caution!
Green Amethyst Daily Cleaning & Care Tips
- Avoid prolonged exposure to sunlight to prevent color fading, especially for heat-treated green amethyst.
- Use mild soapy water and a soft cloth for cleaning. Avoid ultrasonic cleaning.
- Store separately from harder gemstones (e.g., diamonds) to prevent scratches.
Green Amethyst Related FAQs
Is Green Amethyst Natural?
Not entirely. Most green amethyst on the market is created through heat treatment of amethyst. Natural untreated Prasiolite is extremely rare.
Is Green Amethyst from Heat-Treated Amethyst Fake?
No. Natural Prasiolite forms when amethyst undergoes high-temperature or radiation exposure deep within the Earth’s crust, leading to a color transformation. Similarly, heat-treated green amethyst is created by subjecting amethyst to controlled heating or irradiation. Therefore, it is not considered fake.
What is the Difference Between Natural Prasiolite and Treated Green Amethyst?
Formation Environment: Natural Prasiolite color transformation occurs naturally underground. Treated Green Amethyst color is altered through human intervention.
Color: Natural Prasiolite is usually pale green with yellowish or grayish tones and has an uneven distribution of color. Treated green amethyst tends to have a more uniform and vibrant green color.
Additionally, natural Prasiolite is more color-stable, while treated green amethyst is more prone to fading due to temperature changes.
Is Lab-Created Green Amethyst Fake?
No. Lab-created green amethyst is made using the same chemical composition as natural Prasiolite. It possesses the exact same physical and chemical properties as natural Prasiolite. Explore our guide Lab-Created vs. Natural Gemstones for details.
How to Identify Fake Green Amethyst (e.g., glass imitations)?
Imitations are often too pure, have no inclusions (except for lab-created green amethyst), and do not display natural quartz characteristics under optical or UV fluorescence tests.
Does Green Amethyst Fade Over Time?
Green Amethyst sun exposure may cause lightening, but normal wear has minimal impact.
Some heat-treated Green Amethyst may temporarily turn purple in low temperatures (around -20°C) due to reversible oxidation states of iron but will return to green at room temperature. This phenomenon can be used for an experimental observation (handle with caution).
Does Natural Prasiolite Fade?
Natural Prasiolite is more stable than heat-treated green amethyst but can still fade if exposed to prolonged strong sunlight or high temperatures. To maintain its color, it’s best to avoid direct and prolonged sun exposure.
Now that you’ve learned more about green amethyst, are you intrigued by its beauty? Explore our amethyst rings collection, which features stunning green amethyst pieces! 💚✨