New
1.65kg boulder opal specimens rough of 2 pieces from Winton, Australia with blue veining and golden concentric eye formations through natural banded ironstone. Natural, untreated.
1.65kg boulder opal specimens rough 2pc RP251

Boulder Opal Specimen

This 1.65 kilogram parcel contains 2 large boulder opal specimens from the Winton opal fields in Queensland, Australia. These substantial slabs offer serious volume for a cutter seeking major project stones, or a collector wanting an impressive pair of natural display specimens.

Both slabs are crossed by networks of blue opal veins running through warm brown and golden ironstone in natural branching fracture patterns. The top piece shows a prominent golden concentric eye formation in the upper left, with blue veining trailing across the center and lower portion of the slab. The bottom piece carries a similar pattern with a large golden ring formation on the left side and a broad blue and grey opal window running through the right section, along with a secondary concentric eye near the base.

Both specimens display the rich banded ironstone that Winton is known for, with warm honey and rust tones creating strong natural contrast against the cooler blue opal veining. At this scale, each slab offers multiple potential cutting zones, giving a skilled cutter the chance to work several finished cabochons from each piece.

This pair suits experienced lapidary artists working on larger projects, or collectors wanting a matched set of substantial Winton boulder opal specimens.

Both opals are 100% natural and completely untreated. These are not doublets or triplets. Photographs were taken wet under natural sunlight on a phone camera. Dry appearance will differ. Price includes worldwide registered shipping.

This collection will arrive securely packaged in an Opal Galaxy gift box, making it ready for safe storage, jewelry setting, or presentation as a collector gemstone.

Learn about Opal Cutting 

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 $4000
Extra Cost $25 EMS Shipping Upgrade under $200
Extra Cost $10 EMS Shipping Upgrade under $999
Extra Cost $100 FedEx Shipping Upgrade under $3999

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.

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Boulder Opal Specimens Rough 1.65kg

AU$216

In stock

Details

Dimension:

See ruler in image

Weight:

1.65 kilogram total weight

Type:

Natural Solid Untreated Boulder Opal

Source:

Winton, QLD, Australia

Sku:

RP251

Notes

Quantity: 2 piece
Large Boulder Opal Specimen ideal for cutting. Opal is wet to show color and taken under natural sunlight on a phone camera. Price includes Worldwide registered shipping.

Boulder Opal Specimen

This 1.65 kilogram parcel contains 2 large boulder opal specimens from the Winton opal fields in Queensland, Australia. These substantial slabs offer serious volume for a cutter seeking major project stones, or a collector wanting an impressive pair of natural display specimens.

Both slabs are crossed by networks of blue opal veins running through warm brown and golden ironstone in natural branching fracture patterns. The top piece shows a prominent golden concentric eye formation in the upper left, with blue veining trailing across the center and lower portion of the slab. The bottom piece carries a similar pattern with a large golden ring formation on the left side and a broad blue and grey opal window running through the right section, along with a secondary concentric eye near the base.

Both specimens display the rich banded ironstone that Winton is known for, with warm honey and rust tones creating strong natural contrast against the cooler blue opal veining. At this scale, each slab offers multiple potential cutting zones, giving a skilled cutter the chance to work several finished cabochons from each piece.

This pair suits experienced lapidary artists working on larger projects, or collectors wanting a matched set of substantial Winton boulder opal specimens.

Both opals are 100% natural and completely untreated. These are not doublets or triplets. Photographs were taken wet under natural sunlight on a phone camera. Dry appearance will differ. Price includes worldwide registered shipping.

This collection will arrive securely packaged in an Opal Galaxy gift box, making it ready for safe storage, jewelry setting, or presentation as a collector gemstone.

Learn about Opal Cutting 

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 $4000
Extra Cost $25 EMS Shipping Upgrade under $200
Extra Cost $10 EMS Shipping Upgrade under $999
Extra Cost $100 FedEx Shipping Upgrade under $3999

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.

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