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Boulder Opal Gemstones

Discover natural boulder opal gemstones featuring vivid color play set in distinctive ironstone matrix.

Boulder Opal Weight
Boulder Opal Size
Boulder Opal Clarity
Boulder Opal Price

Size Explained

Choose Size or Size Range
For Example: 6-7
For Example: 8-9
Bi-color
Black
Blue
Brown
Golden
Gray
Green
Multicolor Boulder Opal
Orange
Pink
Purple
Red
Turquoise
Violet
White
Yellow
Single
Pairs
Lots
Faceted
Cabochons
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34.16ct Multicolor Boulder Opal, Oval, Opaque

23.4 x 19.6 mm

$ 262.36

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30.94ct Multicolor Boulder Opal, Fancy, Opaque

25.4 x 20.1 mm

$ 169.49

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21.16ct Multicolor Boulder Opal, Fancy, Opaque

25.6 x 16.9 mm

$ 105.38

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20.80ct Multicolor Boulder Opal, Fancy, Opaque

32.3 x 16.8 mm

$ 113.94

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15.88ct Multicolor Boulder Opal, Cushion, Opaque

23.1 x 12.2 mm

$ 110.71

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19.94ct Multicolor Boulder Opal, Marquise, Opaque

36.4 x 16.3 mm

$ 109.23

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20.10ct Multicolor Boulder Opal, Cushion, Opaque

21.1 x 16.6 mm

$ 100.10

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33.71ct Multicolor Boulder Opal, Fancy, Opaque

32.6 x 22.1 mm

$ 184.67

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21.82ct Multicolor Boulder Opal, Cushion, Opaque

20.7 x 16.1 mm

$ 167.34

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42.73ct Multicolor Boulder Opal, Oval, Opaque

27 x 20 mm (calibrated)

$ 327.70

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20.55ct Multicolor Boulder Opal, Pear Shape, Opaque

31.9 x 16.1 mm

$ 112.58

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17.03ct Multicolor Boulder Opal, Fancy, Opaque

26.9 x 13.5 mm

$ 93.29

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16.81ct Multicolor Boulder Opal, Fancy, Opaque

28.8 x 13.1 mm

$ 83.71

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35.99ct Multicolor Boulder Opal, Fancy, Opaque

45 x 23.8 mm

$ 107.53

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21.39ct Multicolor Boulder Opal, Cushion, Opaque

16 x 16 mm (calibrated)

$ 164.04

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30.50ct Multicolor Boulder Opal, Pear Shape, Translucent

30 x 22 mm (calibrated)

$ 167.08

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14.98ct Multicolor Boulder Opal, Cushion, Opaque

20.2 x 13.9 mm

$ 87.03

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41.37ct Multicolor Boulder Opal, Oval, Opaque

30 x 22 mm (calibrated)

$ 226.63

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5.79ct Multicolor Boulder Opal, Fancy, Opaque

18.6 x 9 mm

$ 24.03

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36.66ct Multicolor Boulder Opal, Oval, Opaque

39.1 x 16.4 mm

$ 200.83

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11.61ct Multicolor Boulder Opal, Fancy, Opaque

18.8 x 12.3 mm

$ 34.69

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10.36ct Multicolor Boulder Opal, Fancy, Translucent

19.6 x 11.4 mm

$ 51.59

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9.73ct Multicolor Boulder Opal, Fancy, Opaque

16 x 12 mm (calibrated)

$ 48.46

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8.60ct Multicolor Boulder Opal, Pear Shape, Opaque

18.9 x 12.5 mm

$ 65.95

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Why Buy Boulder Opal from GemSelect?

Natural Boulder Opal Gemstones

Our natural boulder opal gemstones are sourced primarily from Australia and cut to preserve the stone’s natural ironstone backing and vibrant play of color.

Australian Boulder Opal Stones

Australian boulder opal is prized for its organic patterns, durability, and striking contrast between opal color and ironstone matrix, making each stone one of a kind.

Natural Boulder Opal Gemstones from Australia

Boulder Opal for Jewelry

Boulder opal is ideal for rings, pendants, and statement jewelry thanks to its natural backing, which provides added strength compared to many other opal types.

Loose Boulder Opal Stones

Buying loose boulder opal allows full creative freedom for custom jewelry designs, from freeform cabochons to polished statement pieces.

Boulder Opal Cabochons

Boulder opal is most commonly cut as cabochons to highlight its natural patterns and flowing color veins within the ironstone.

Unique Patterns and Color Play

Each boulder opal displays individual color flashes ranging from blue and green to fiery reds, often following natural seams within the host rock.

Wholesale Boulder Opal

We offer competitive pricing on boulder opal gemstones for jewelers, designers, and collectors seeking distinctive stones in larger quantities.

Learn more about opal varieties, properties, and care on our Opal Information Page.

FAQs

What is boulder opal?

Boulder opal is a natural opal found within ironstone, typically cut with part of the host rock attached to enhance durability and appearance.

Is boulder opal stronger than other opals?

Yes, the ironstone backing makes boulder opal more durable than many solid opals, making it well suited for everyday jewelry.

Are your boulder opals natural?

All our boulder opal gemstones are 100% natural. Any treatments, if present, are clearly disclosed.

Where does boulder opal come from?

Most boulder opal comes from Queensland, Australia, one of the world’s most important sources of this unique gemstone.

Is boulder opal good for rings?

Yes, boulder opal is a popular choice for rings due to its natural strength and striking appearance, especially in protective settings.

GemSelect Certified Store Reviews

GemSelect: Over 22 Years in the Gemstone Business! Thank you for trusting us with your purchase!

Overall Rating -> 9 star ratings

Plan on purchasing on an ongoing basis. So far.....so good....

Posted By Jim in January, 2026
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Overall Rating -> 10 star ratings

Great experience. I can't wait to explore on the website further.

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Overall Rating -> 9 star ratings

The purchasing process is fairly quick and straightforward and for me user friendly so it probably took more or less than 3 minutes to purchase and pay for the items. I wish there was a discount offer for multiple items to encourage us buyers to purchase more an incentive and add more sales in your end. Besides that, it's been a great purchasing experience and will continue to shop as I am a repeat customer and have bought from your store many times before. Thank you.

Posted By Emmanuel in October, 2025
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Overall Rating -> 8 star ratings

Site worked well and helped me find a rock that matched what I was looking for. Well within budget and I trust it will show up, so that's definitely positive. Not much else to it. Satisfied.

Posted By Big Ricky in May, 2026
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Overall Rating -> 10 star ratings

Very large selection from affordable to high end I will be coming back to shop again!

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Overall Rating -> 10 star ratings

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Posted By Mel in February, 2026
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Enlarged Gemstone Image