Emerald vs. Peridot: A Gemstone Comparison
Emerald and Peridot are two green gemstones that can sometimes be confused for one another (especially when the emerald is at the yellow end of the green spectrum). While both display striking green hues, their origins, compositions, and values differ significantly.
Historically, Emerald has been one of the most prized gemstones, adorning royal and religious jewellery for centuries. Peridot, on the other hand, has quiet a history of being mistaken for Emerald. A great example of this is the Shrine of the Three Kings in Cologne Cathedral, Germany, that was believed to have been decorated in emeralds, but when tested the green gemstones turned out to be Peridots.
Despite their shared green colour, these two gemstones have distinct characteristics that set them apart. Understanding their differences is crucial whether you're a jeweller looking for the perfect green gem or a collector seeking something special.
So let’s explore the key distinctions between Emerald and Peridot, from their gemmological properties to their symbolic meanings.
How to Tell the Difference: Visual & Gemmological Tests
Visual Clues
Emerald: Deep green, often with bluish undertones. The colour can range from a light green to a rich, velvety forest green and the stone will almost always be included (only the truly high end and super rare stones will be eye clean)
Peridot: Yellow-green to olive green, with a warm, golden undertone. It never displays the bluish-green hue seen in some Emeralds and is usually less included, or eye clean.
Gemmological Tests
| Test | Emerald | Peridot |
|---|---|---|
| Refractive Index (RI) | 1.577–1.583 (+/- 0.017) | 1.654–1.690 (+/- 0.020) |
| Birefringence | 0.005–0.009 | 0.035–0.038 (Can cause a 'seeing double' effect when looking through the stones table at the pavilion facets) |
| Pleochroism | Moderate to Strong (yellowish-green and bluish-green) | None or Weak |
| UV Fluorescence | Can be none, but could also be Moderate | None |
| Optical Character | Doubly refractive, uniaxial negative | Doubly refractive, biaxial positive or negative |
Colour
Emerald: A saturated green caused by trace amounts of chromium and vanadium. It often exhibits colour zoning and can have a bluish tint.
Peridot: Always a yellow-green or olive green due to the presence of iron. It never has a bluish tint like Emerald.
Clarity & Inclusions
Emerald: A Type 3 gemstone, meaning it is almost always included. Common inclusions are garden-like formations called ‘jardin’ (French for garden), made up of liquid-filled fractures, gas bubbles, or other minerals.
Peridot: A Type 2 gemstone, meaning it usually has fewer inclusions than Emerald. It may contain small ‘lily pad’ inclusions (disc-like fractures around crystals), which are an identification marker as they are a type of inclusion that is unique to peridot.
Gemstone Formation
Emerald: A variety of beryl, formed in hydrothermal veins and metamorphic rocks. Found in Colombia, Zambia, and Brazil.
Peridot: A variety of the mineral olivine, formed deep in the Earth's mantle and brought to the surface by volcanic activity. Found in Myanmar, Arizona, and China. It has also been discovered in pallasite meteorites.
Durability & Wearability
Scratch Resistance (Mohs Hardness Scale):
Emerald: 7.5–8 (Good level of scratch resistance for daily wear)
Peridot: 6.5–7 (Ok level of scratch resistance, but it is below the level of dust so can start to look dull over time)
Cleavage & Toughness:
Emerald: No true cleavage, but brittle with poor toughness due to natural fractures, requiring care in jewellery settings.
Peridot: No true cleavage, fair to good toughness, but can be brittle under impact.
Best Use: Emerald is best suited for jewellery with protective settings that's unlikely to be knocked about, such as pendants and earrings. Peridot is durable enough for rings but should be worn with care to avoid scratches.
Enhancements & Treatments
Emerald: Almost always treated with oil or resin to enhance clarity and reduce the appearance of inclusions.
Peridot: Rarely treated, as its clarity is naturally good.
Both Emerald and Peridot can be synthesized, and lab-grown versions are available on the market.
Price Comparison
Emerlad: Price can range quiet a bit, from as cheap as £5 per carat for really poor quality, opaque stones, to £10,000+ for large high quality stones.
Peridot: Much more affordable, with prices ranging from £10–£500 per carat.
Size
Emerald: Most faceted emeralds fall between 0.50 to 5 carats, with larger stones being rarer due to natural inclusions and fractures.
Peridot: Tends to be more commonly found in larger sizes, with most faceted peridots ranging from 1 to 10 carats, although smaller sizes do tend to be readily available.
Rarity & Sourcing
Emerald: Found in Colombia, Zambia, and Brazil, with Colombian Emeralds being the most sought-after for their deep green hue.
Peridot: Mined in Myanmar, the USA (Arizona), and Pakistan.
Cut & Shape Preferences
Emerald: Commonly cut into emerald-cut (rectangles), oval, and cushion shapes to enhance its colour and reduce stress on natural fractures.
Peridot: Often cut into ovals, rounds, and cushions, with faceting styles designed to maximise brilliance/sparkle.
Symbolic & Spiritual Associations
Emerald: Linked to love, wisdom, and prosperity. Historically regarded as a stone of protection and foresight.
Peridot: Associated with warmth, positivity, and abundance. Believed to bring good fortune and ward off negativity.
Comparison Summary
| Feature | Emerald | Peridot |
| Hardness | 7.5–8 | 6.5–7 |
| Cleavage | None, but brittle | None, but brittle |
| Colour | Shades of green, often with blue tones | Yellow-green to olive green |
| Commonly Included? | Type 3 - Heavily included | Type 2 - Somewhat included |
| Common Treatments | Oiling, resin filling | Rarely treated |
| Price per Carat | £5–£10,000+ | £10–£500 |
| Rarity | High-quality is rare | More common |
| Large Sizes? (5 ct+) | Available but costly | Readily available |
| Associated With | Love, wisdom, prosperity | Positivity, abundance, protection |
Emerald and Peridot may both be green, but their differences in durability, clarity, and rarity make them unique choices for jewellers and collectors.
If you’re looking for a prestigious, richly coloured gemstone with historical significance, Emerald is an excellent choice. However, if you prefer a more affordable, vibrant green gemstone with excellent natural clarity, Peridot is a fantastic alternative. Either way, both stones bring a striking green brilliance to any jewellery piece!
