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Boulder Opal Necklace 25ct Green Orange Blue Sterling Silver

This solid untreated Australian boulder opal necklace in sterling silver is an exquisite 25ct birthstone necklace displaying vibrant play of color with vivid flashes of neon green, golden yellow, fiery orange, and electric blue across authentic ironstone matrix. Expertly bezel set horizontally into a sleek sterling silver setting, this natural Australian gemstone jewelry piece is ready for daily wear.

Design and Craftsmanship

  • Horizontal Bezel Setting: A sleek sterling silver bezel holds the curved 25ct boulder opal horizontally along the neckline for a balanced modern look.

  • Natural Ironstone Backing: The reverse side reveals the rich chocolate ironstone host rock matrix, confirming this is a genuine solid Australian gemstone completely free from artificial doublets.

  • Adjustable Chain with S925 Heart Charm: Fitted with a durable chain, secure lobster clasp, and an adjustable extender ending in a stamped S925 sterling silver heart charm.

October Birthstone Necklace

Opal is the traditional birthstone for October. A genuine 25ct Australian boulder opal necklace with rainbow fire makes a memorable gift for birthdays, anniversaries, or fine jewelry collections.

About Queensland Boulder Opal Fields

Mined in remote outback Queensland, Australian boulder opal forms within cracks and voids inside ironstone boulders over millions of years. The natural dark ironstone backing provides great durability and creates rich contrast that makes the precious opal colors stand out.

Authenticity

Solid natural untreated Australian boulder opal. Guaranteed completely free from synthetic treatments, dye, smoke enhancements, doublets, or triplets.

Official certificate available upon request. Authentic & Trusted Opal Certification by Opal Galaxy

Learn more

 What Makes an Opal Valuable| Australian Opal Buying Guide | Which Star Signs Should Wear Opal?

Browse all Silver Boulder Opal Pendants collection or contact us with questions.

Shipping Updates - March 2026

Latest international delivery information from Australia Post and FedEx.

USA Tariff 

USA customers do not need to pay any tariffs on their purchase. Opal Galaxy covers all tariff charges to the USA, with no additional government fees added after checkout.

Delivery Status

USA: No delays
Asia: No delays
UK: Minor delays possible (Complimentary EMS Express upgrade)
Europe: Minor delays possible (Complimentary EMS Express upgrade)
Middle East: Shipping temporarily suspended - Please contact us to discuss shipping arrangements before purchase.

Shipping Information

All shipping includes complimentary insurance.

Registered Shipping $15 under $200
Free Registered Shipping over $201
Free Worldwide EMS Express Shipping over $1000
Free Worldwide FedEx Shipping over $5000
Extra Cost $25 EMS Shipping Upgrade under $200
Extra Cost $10 EMS Shipping Upgrade under $999
Extra Cost $100 FedEx Shipping Upgrade under $4999

Please view our Shipping Policy page for more information.

7 day return and refund policy.
Please view our Return and Refund page for more information.

We offer a lifetime guarantee for natural cracks that may form in our opals.
There is a very low chance that this can happen, however occasionally it might.
Our guarantee excludes any opals sold with existing fractures.
Please view our Terms and Conditions.

Caring for Your Australian Opal

Opal Jewelry

Important: Opals Are Fragile Gemstones
Opals are softer than sapphires, rubies, or diamonds and will crack or chip if struck hard against solid surfaces.

Always remove opal jewelry before:
Sports or physical activities
Manual labor, gardening, or gym workouts
Household tasks where impact is possible (lifting, moving furniture, etc.)

Even a minor knock during everyday wear can cause permanent damage. Treat opals as delicate gemstones, not everyday workwear.

Cleaning Your Opal

Clean with warm water and mild soap. Avoid harsh chemicals like bleach, ammonia, or chlorine. Light exposure to hand soap or dishwashing detergent is safe.

Storage

Store opal jewelry separately from harder gemstones (diamonds, sapphires) to prevent scratching.

Solid Natural Opals

(Black, Boulder, Crystal, White Opal)
Natural solid opals are stable and won't change color or crack from water, humidity, or temperature changes. They are safe to submerge in water and can be worn daily, provided they are protected from physical impact. Solid opals are a single piece of gemstone with no artificial backing, making them ideal for heirloom quality jewelry when handled with care.

Opal Doublets

Opal doublets consist of a thin slice of natural opal bonded to a dark backing. Do not submerge doublets in water as prolonged exposure can weaken the adhesive bond and cause separation or cloudiness. Remove doublet jewelry before swimming, bathing, or washing dishes. Clean with a damp cloth only; do not soak or use ultrasonic cleaners.

Like all opals, doublets are fragile and must be protected from impact.

Not sure which type you have? Solid opals show natural color throughout the stone. Doublets have a visible dark backing layer when viewed from the side.

Boulder Opal Necklace 25ct Green Orange Blue Sterling Silver

Original price was: AU$322.Current price is: AU$273.

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Details

Dimension:

 10x19x5 mm

Weight:

 25 ctw (Pendant and Necklace)

Type:

 Natural Solid Untreated Boulder Opal

Source:

 Winton, QLD, Australia

Sku:

 NN733

Notes

Necklace: 18 inch (slightly adjustable)
Metal: 925 sterling silver pendant and necklace (stamped)

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