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Home Collections Loose Boulder Opal Cabochons for Jewelry Making

Loose Boulder Opal Cabochons for Jewelry Making

Loose boulder opal cabochons for jewelry making - sourced from the rugged opal fields of Queensland, Australia - offering endless creative possibilities for artisans and jewelry makers.

Loose Boulder Opal Cabochons for Jewelry Making Weight
Loose Boulder Opal Cabochons for Jewelry Making Size
Loose Boulder Opal Cabochons for Jewelry Making Clarity
Loose Boulder Opal Cabochons for Jewelry Making Price

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Multicolor Loose Boulder Opal Cabochons for Jewelry Making
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8.30ct Multicolor Boulder Opal, Pear Shape, Opaque

19.3 x 11 mm

$ 63.65

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11.51ct Multicolor Boulder Opal, Pear Shape, Opaque

26.8 x 14.6 mm

$ 57.32

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31.20ct Multicolor Boulder Opal, Pear Shape, Opaque

29.5 x 20.6 mm

$ 239.28

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9.46ct Multicolor Boulder Opal, Pear Shape, Opaque

17.9 x 12 mm

$ 65.95

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10.40ct Multicolor Boulder Opal, Fancy, Opaque

19.5 x 12.6 mm

$ 79.76

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12.31ct Multicolor Boulder Opal, Oval, Opaque

25.9 x 17.1 mm

$ 61.30

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8.27ct Multicolor Boulder Opal, Fancy, Opaque

27.2 x 8.3 mm

$ 41.18

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3.16ct Multicolor Boulder Opal, Cushion, Opaque

9.7 x 7.6 mm

$ 13.11

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7.48ct Multicolor Boulder Opal, Pear Shape, Opaque

16 x 12 mm (calibrated)

$ 52.15

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7.95ct Multicolor Boulder Opal, Oval, Opaque

18.3 x 9.9 mm

$ 55.43

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10.92ct Multicolor Boulder Opal, Fancy, Opaque

22.6 x 12.9 mm

$ 54.38

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7.30ct Multicolor Boulder Opal, Pear Shape, Opaque

15 x 9.5 mm

$ 50.90

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17.56ct Multicolor Boulder Opal, Fancy, Opaque

24 x 16.7 mm

$ 87.45

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6.16ct Multicolor Boulder Opal, Fancy, Opaque

16.7 x 9.7 mm

$ 30.68

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11.24ct Multicolor Boulder Opal, Fancy, Opaque

16.7 x 13.8 mm

$ 55.98

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54.71ct Multicolor Boulder Opal, Oval, Opaque

27.3 x 23.3 mm

$ 419.58

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23.34ct Multicolor Boulder Opal, Oval, Opaque

20.8 x 14 mm

$ 179.00

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2.95ct Multicolor Boulder Opal, Pear Shape, Opaque

11.5 x 8.5 mm

$ 12.24

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13.29ct Multicolor Boulder Opal, Fancy, Opaque

21.7 x 13.6 mm

$ 66.18

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7.81ct Multicolor Boulder Opal, Pear Shape, Opaque

16.4 x 10.5 mm

$ 59.90

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10.26ct Multicolor Boulder Opal, Fancy, Opaque

19.2 x 10.5 mm

$ 51.09

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13.03ct Multicolor Boulder Opal, Pear Shape, Opaque

22.4 x 13.3 mm

$ 64.89

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8.11ct Multicolor Boulder Opal, Pear Shape, Opaque

21.1 x 11 mm

$ 56.54

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8.69ct Multicolor Boulder Opal, Pear Shape, Translucent

20 x 12.3 mm

$ 66.64

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Why Buy Loose Boulder Opal Cabochons For Jewelry Making from GemSelect?

What Are Boulder Opal Cabochons?

Boulder opal is a unique variety of opal that forms naturally within ironstone or sandstone matrix, creating a durable and grounded base for the opal's signature iridescent play-of-color. Unlike solid opals, boulder opals require at least 5mm of genuine opal to qualify as such, making them more resilient for everyday jewelry. Our loose cabochons are carefully hand-cut to preserve the stone's natural flow and patterns, ensuring each piece tells its own geological story.

  • Origin: Primarily from Queensland, Australia, including regions like Quilpie and Winton.
  • Formation: Millions of years in the making, often within fossilized wood or ironstone roots for one-of-a-kind patterns.
  • Cut Style: Smooth, domed cabochons (non-faceted) to enhance light refraction and color flashes.
Loose Boulder Opal Cabochons for Jewelry Making

Why Choose Boulder Opal for Your Designs?

Boulder opal cabochons are a favorite among jewelry makers for their affordability, durability, and artistic versatility. The ironstone backing adds strength, reducing the risk of cracking compared to thinner solid opals. With water content typically between 6-10%, these stones are more stable in varying climates but still benefit from gentle care.

Feature Benefit
Vibrant Color Play Shimmering flashes of blue, green, gold, and red for eye-catching pieces.
Durability Matrix support makes them ideal for rings and brooches; Mohs hardness 5.5-6.5.
Ethical Sourcing Hand-mined by small family teams in Australia, ensuring sustainable practices.
Versatility Available in sizes from 5x3mm to 30x15mm; freeform or calibrated shapes.

Care Tips and Symbolic Meaning

To keep your boulder opal cabochons shining, clean with warm soapy water and a soft brush. Avoid harsh chemicals, ultrasonic cleaners, or prolonged dry storage-store in an airtight container with a damp cloth if needed. Symbolically, boulder opals represent grounding energy, creativity, and emotional balance, making them perfect for inspirational jewelry.

"Each boulder opal is a tiny universe captured in stone-unique, resilient, and full of hidden fire."

FAQs

What makes boulder opal cabochons different from other opal types?

Boulder opal cabochons are unique due to their natural ironstone or sandstone matrix, which provides durability and distinctive patterns. Unlike solid opals, they combine a robust backing with vibrant opal color play, making them ideal for jewelry making. They typically have a Mohs hardness of 5.5-6.5, offering greater resistance to wear compared to thinner opals.

Are your boulder opal cabochons ethically sourced?

Yes, our boulder opals are hand-mined from Queensland, Australia, by small family-run operations. We prioritize sustainable and ethical sourcing practices to ensure minimal environmental impact and fair working conditions.

What sizes and shapes of boulder opal cabochons are available?

We offer a variety of sizes ranging from 5x3mm to 30x15mm, available in both freeform and calibrated shapes like ovals, rounds, and teardrops. Each cabochon is hand-cut to highlight its unique color play and natural matrix patterns.

How should I care for my boulder opal cabochons?

To maintain their brilliance, clean boulder opal cabochons with warm soapy water and a soft brush. Avoid harsh chemicals, ultrasonic cleaners, or prolonged dry storage. Store in an airtight container with a damp cloth to prevent dehydration, as they contain 6-10% water content.

Can I use boulder opal cabochons for all types of jewelry?

Absolutely! Their durability makes them suitable for rings, pendants, earrings, and brooches. The ironstone matrix adds strength, but for high-impact pieces like rings, consider protective settings to enhance longevity.

All stones are natural, untreated, and come with a certificate of authenticity.

GemSelect Certified Store Reviews

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Overall Rating -> 7 star ratings

Overall the site is good to use and simple to navigate for what i needed and i liked that they are clear and detailed on the size shape and cut of the stones only input id like is for stones that have a specific refractive quality like moonstone in my case if theyd showcase the cut stones refraction so you know how it looks when buying

Posted By Revenant in August, 2026
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