search
  • Sign In
    Sign Up

  • English speaking customer support only

    1-800-464-1640

    International:

    +66-39601289

  • Change Language
  • USD
  • CART
FREE SHIPPING
Australian Boulder Opal for Sale, Natural Opals in Stock

Australian Boulder Opal for Sale | Natural Opals in Stock

We're proud to present our unique selection of natural Boulder Opal for sale. Boulder Opal has an earthy brown base-color mixed with the whole color spectrum of opal. This is the perfect gemstone for jewelry designers and hobby jewelers as well. We stock Boulder Opals in a large variety of shapes, sizes and price ranges. Use the filters on this page to quickly select the perfect fitting Boulder Opal for your jewelry needs. We ship our gemstones worldwide with a variety of shipping options.
Boulder Opal Weight Boulder Opal Size Boulder Opal Clarity Boulder Opal Price Boulder Opal Origin
More
Boulder Opal Single
Boulder Opal Pairs
Boulder Opal Lots
Boulder Opal Faceted
Boulder Opal Cabochons
Size Ranges Calibrated Sizes
Sort By:
Clear All
Photos are of Actual Products for Sale
30.50ct Loose Boulder Opal | 30.5 carat Pear Boulder Opal, loose Certified Boulder Opal from Australia, Natural Untreated Gem, 29.4 x 21.8 mm, Photo A
Click for Product Video (523672)

30.5 carat Pear Boulder Opal, loose Certified Boulder Opal from Australia, Natural Untreated Gem, 29.4 x 21.8 mm

Natural Boulder Opal, Qty: 1 pc | 30.50 carat weight Boulder Opal

30.50ct1 Piece
$ 167.75
29.4 x 21.8 mm
Item Description
Stone Type: Loose Boulder Opal
Boulder Opal Weight: 30.50 ct Boulder Opal
Boulder Opal Shape: Pear Cabochon Boulder Opal
Boulder Opal Size: 29.4 x 21.8 mm Boulder Opal
Boulder Opal Color: Multicolor Boulder Opal
Boulder Opal Clarity: Translucent Boulder Opal
Boulder Opal Origin: Australia Boulder Opal
Boulder Opal Treatment: Untreated
Boulder Opal Quantity: 1
Boulder Opal Certificate: GemSelect
Product Description:
View Details
Add to Cart
35.80ct Loose Boulder Opal | 35.8 ct Fancy Boulder Opal, 36.6 x 19.7 mm From Australia, Photo A
Click for Product Video (575232)

35.8 ct Fancy Boulder Opal, 36.6 x 19.7 mm From Australia

Natural Boulder Opal, Qty: 1 pc | 35.80 carat weight Boulder Opal

35.80ct1 Piece
$ 118.14
36.6 x 19.7 mm
Item Description
Stone Type: Loose Boulder Opal
Boulder Opal Weight: 35.80 ct Boulder Opal
Boulder Opal Shape: Fancy Cabochon Boulder Opal
Boulder Opal Size: 36.6 x 19.7 mm Boulder Opal
Boulder Opal Color: Multicolor Boulder Opal
Boulder Opal Clarity: Opaque Boulder Opal
Boulder Opal Origin: Australia Boulder Opal
Boulder Opal Treatment: Untreated
Boulder Opal Quantity: 1
Boulder Opal Certificate: GemSelect
Product Description:
View Details
Add to Cart
21.16ct Loose Boulder Opal | 21.16 ct Fancy Boulder Opal, 25.6 x 16.9 mm From Australia, Photo A
Click for Product Video (678766)

21.16 ct Fancy Boulder Opal, 25.6 x 16.9 mm From Australia

Natural Boulder Opal, Qty: 1 pc | 21.16 carat weight Boulder Opal

21.16ct1 Piece
$ 105.80
25.6 x 16.9 mm
Item Description
Stone Type: Loose Boulder Opal
Boulder Opal Weight: 21.16 ct Boulder Opal
Boulder Opal Shape: Fancy Cabochon Boulder Opal
Boulder Opal Size: 25.6 x 16.9 mm Boulder Opal
Boulder Opal Color: Multicolor Boulder Opal
Boulder Opal Clarity: Opaque Boulder Opal
Boulder Opal Origin: Australia Boulder Opal
Boulder Opal Treatment: Untreated
Boulder Opal Quantity: 1
Boulder Opal Certificate: GemSelect
Product Description:
View Details
Add to Cart
20.55ct Loose Boulder Opal | 20.55 carat Pear Boulder Opal, loose Certified Boulder Opal from Australia, Natural Untreated Gem, 31.9 x 16.1 mm, Photo A

20.55 carat Pear Boulder Opal, loose Certified Boulder Opal from Australia, Natural Untreated Gem, 31.9 x 16.1 mm

Natural Boulder Opal, Qty: 1 pc | 20.55 carat weight Boulder Opal

20.55ct1 Piece
$ 113.03
31.9 x 16.1 mm
Item Description
Stone Type: Loose Boulder Opal
Boulder Opal Weight: 20.55 ct Boulder Opal
Boulder Opal Shape: Pear Cabochon Boulder Opal
Boulder Opal Size: 31.9 x 16.1 mm Boulder Opal
Boulder Opal Color: Multicolor Boulder Opal
Boulder Opal Clarity: Opaque Boulder Opal
Boulder Opal Origin: Australia Boulder Opal
Boulder Opal Treatment: Untreated
Boulder Opal Quantity: 1
Boulder Opal Certificate: GemSelect
Product Description:
View Details
Add to Cart
33.73ct Loose Boulder Opal | 33.73 ct Fancy Boulder Opal, 35.2 x 23.5 mm From Australia, Photo A
Click for Product Video (524127)

33.73 ct Fancy Boulder Opal, 35.2 x 23.5 mm From Australia

Natural Boulder Opal, Qty: 1 pc | 33.73 carat weight Boulder Opal

33.73ct1 Piece
$ 185.52
35.2 x 23.5 mm
Item Description
Stone Type: Loose Boulder Opal
Boulder Opal Weight: 33.73 ct Boulder Opal
Boulder Opal Shape: Fancy Cabochon Boulder Opal
Boulder Opal Size: 35.2 x 23.5 mm Boulder Opal
Boulder Opal Color: Multicolor Boulder Opal
Boulder Opal Clarity: Translucent Boulder Opal
Boulder Opal Origin: Australia Boulder Opal
Boulder Opal Treatment: Untreated
Boulder Opal Quantity: 1
Boulder Opal Certificate: GemSelect
Product Description:
View Details
Add to Cart
30.94ct Loose Boulder Opal | 30.94 ct Fancy Boulder Opal, 25.4 x 20.1 mm From Australia, Photo A
Click for Product Video (521754)

30.94 ct Fancy Boulder Opal, 25.4 x 20.1 mm From Australia

Natural Boulder Opal, Qty: 1 pc | 30.94 carat weight Boulder Opal

30.94ct1 Piece
$ 170.17
25.4 x 20.1 mm
Item Description
Stone Type: Loose Boulder Opal
Boulder Opal Weight: 30.94 ct Boulder Opal
Boulder Opal Shape: Fancy Cabochon Boulder Opal
Boulder Opal Size: 25.4 x 20.1 mm Boulder Opal
Boulder Opal Color: Multicolor Boulder Opal
Boulder Opal Clarity: Opaque Boulder Opal
Boulder Opal Origin: Australia Boulder Opal
Boulder Opal Treatment: Untreated
Boulder Opal Quantity: 1
Boulder Opal Certificate: GemSelect
Product Description:
View Details
Add to Cart
17.24ct Loose Boulder Opal | 17.24 ct Trillion Boulder Opal, 21.2 x 17.4 mm From Australia, Photo A

17.24 ct Trillion Boulder Opal, 21.2 x 17.4 mm From Australia

Natural Boulder Opal, Qty: 1 pc | 17.24 carat weight Boulder Opal

17.24ct1 Piece
$ 86.20
21.2 x 17.4 mm
Item Description
Stone Type: Loose Boulder Opal
Boulder Opal Weight: 17.24 ct Boulder Opal
Boulder Opal Shape: Trillion Cabochon Boulder Opal
Boulder Opal Size: 21.2 x 17.4 mm Boulder Opal
Boulder Opal Color: Multicolor Boulder Opal
Boulder Opal Clarity: Opaque Boulder Opal
Boulder Opal Origin: Australia Boulder Opal
Boulder Opal Treatment: Untreated
Boulder Opal Quantity: 1
Boulder Opal Certificate: GemSelect
Product Description:
View Details
Add to Cart
15.88ct Loose Boulder Opal | 15.88 ct Cushion Boulder Opal, 23.1 x 12.2 mm From Australia, Photo A

15.88 ct Cushion Boulder Opal, 23.1 x 12.2 mm From Australia

Natural Boulder Opal, Qty: 1 pc | 15.88 carat weight Boulder Opal

15.88ct1 Piece
$ 111.16
23.1 x 12.2 mm
Item Description
Stone Type: Loose Boulder Opal
Boulder Opal Weight: 15.88 ct Boulder Opal
Boulder Opal Shape: Cushion Cabochon Boulder Opal
Boulder Opal Size: 23.1 x 12.2 mm Boulder Opal
Boulder Opal Color: Multicolor Boulder Opal
Boulder Opal Clarity: Opaque Boulder Opal
Boulder Opal Origin: Australia Boulder Opal
Boulder Opal Treatment: Untreated
Boulder Opal Quantity: 1
Boulder Opal Certificate: GemSelect
Product Description:
View Details
Add to Cart
42.73ct Loose Boulder Opal | 42.73 ct Oval Boulder Opal, 27.5 x 20.8 mm From Australia, Photo A
Click for Product Video (322037)

42.73 ct Oval Boulder Opal, 27.5 x 20.8 mm From Australia

Natural Boulder Opal, Qty: 1 pc | 42.73 carat weight Boulder Opal

42.73ct1 Piece
$ 329.02
27.5 x 20.8 mm
Item Description
Stone Type: Loose Boulder Opal
Boulder Opal Weight: 42.73 ct Boulder Opal
Boulder Opal Shape: Oval Cabochon Boulder Opal
Boulder Opal Size: 27.5 x 20.8 mm Boulder Opal
Boulder Opal Color: Multicolor Boulder Opal
Boulder Opal Clarity: Opaque Boulder Opal
Boulder Opal Origin: Australia Boulder Opal
Boulder Opal Treatment: Untreated
Boulder Opal Quantity: 1
Boulder Opal Certificate: GemSelect
Product Description:
View Details
Add to Cart
28.58ct Loose Boulder Opal | 28.58 ct Oval Boulder Opal, 23.1 x 18.5 mm From Australia, Photo A
Click for Product Video (300453)

28.58 ct Oval Boulder Opal, 23.1 x 18.5 mm From Australia

Natural Boulder Opal, Qty: 1 pc | 28.58 carat weight Boulder Opal

28.58ct1 Piece
$ 200.06
23.1 x 18.5 mm
Item Description
Stone Type: Loose Boulder Opal
Boulder Opal Weight: 28.58 ct Boulder Opal
Boulder Opal Shape: Oval Cabochon Boulder Opal
Boulder Opal Size: 23.1 x 18.5 mm Boulder Opal
Boulder Opal Color: Multicolor Boulder Opal
Boulder Opal Clarity: Opaque Boulder Opal
Boulder Opal Origin: Australia Boulder Opal
Boulder Opal Treatment: Untreated
Boulder Opal Quantity: 1
Boulder Opal Certificate: GemSelect
Product Description:
View Details
Add to Cart
33.71ct Loose Boulder Opal | 33.71 ct Fancy Boulder Opal, 32.6 x 22.1 mm From Australia, Photo A
Click for Product Video (523722)

33.71 ct Fancy Boulder Opal, 32.6 x 22.1 mm From Australia

Natural Boulder Opal, Qty: 1 pc | 33.71 carat weight Boulder Opal

33.71ct1 Piece
$ 185.41
32.6 x 22.1 mm
Item Description
Stone Type: Loose Boulder Opal
Boulder Opal Weight: 33.71 ct Boulder Opal
Boulder Opal Shape: Fancy Cabochon Boulder Opal
Boulder Opal Size: 32.6 x 22.1 mm Boulder Opal
Boulder Opal Color: Multicolor Boulder Opal
Boulder Opal Clarity: Opaque Boulder Opal
Boulder Opal Origin: Australia Boulder Opal
Boulder Opal Treatment: Untreated
Boulder Opal Quantity: 1
Boulder Opal Certificate: GemSelect
Product Description:
View Details
Add to Cart
19.33ct Loose Boulder Opal | 19.33 ct Fancy Boulder Opal, 26 x 15.9 mm From Australia, Photo A

19.33 ct Fancy Boulder Opal, 26 x 15.9 mm From Australia

Natural Boulder Opal, Qty: 1 pc | 19.33 carat weight Boulder Opal

19.33ct1 Piece
$ 96.65
26 x 15.9 mm
Item Description
Stone Type: Loose Boulder Opal
Boulder Opal Weight: 19.33 ct Boulder Opal
Boulder Opal Shape: Fancy Cabochon Boulder Opal
Boulder Opal Size: 26 x 15.9 mm Boulder Opal
Boulder Opal Color: Multicolor Boulder Opal
Boulder Opal Clarity: Opaque Boulder Opal
Boulder Opal Origin: Australia Boulder Opal
Boulder Opal Treatment: Untreated
Boulder Opal Quantity: 1
Boulder Opal Certificate: GemSelect
Product Description:
View Details
Add to Cart
28.09ct Loose Boulder Opal | 28.09 ct Oval Boulder Opal, 26.6 x 19.4 mm From Australia, Photo A

28.09 ct Oval Boulder Opal, 26.6 x 19.4 mm From Australia

Natural Boulder Opal, Qty: 1 pc | 28.09 carat weight Boulder Opal

28.09ct1 Piece
$ 216.29
26.6 x 19.4 mm
Item Description
Stone Type: Loose Boulder Opal
Boulder Opal Weight: 28.09 ct Boulder Opal
Boulder Opal Shape: Oval Cabochon Boulder Opal
Boulder Opal Size: 26.6 x 19.4 mm Boulder Opal
Boulder Opal Color: Multicolor Boulder Opal
Boulder Opal Clarity: Opaque Boulder Opal
Boulder Opal Origin: Australia Boulder Opal
Boulder Opal Treatment: Untreated
Boulder Opal Quantity: 1
Boulder Opal Certificate: GemSelect
Product Description:
View Details
Add to Cart
25.50ct Loose Boulder Opal | 25.5 ct Trillion Boulder Opal, 22.1 x 21.4 mm From Australia, Photo A

25.5 ct Trillion Boulder Opal, 22.1 x 21.4 mm From Australia

Natural Boulder Opal, Qty: 1 pc | 25.50 carat weight Boulder Opal

25.50ct1 Piece
$ 127.50
22.1 x 21.4 mm
Item Description
Stone Type: Loose Boulder Opal
Boulder Opal Weight: 25.50 ct Boulder Opal
Boulder Opal Shape: Trillion Cabochon Boulder Opal
Boulder Opal Size: 22.1 x 21.4 mm Boulder Opal
Boulder Opal Color: Multicolor Boulder Opal
Boulder Opal Clarity: Opaque Boulder Opal
Boulder Opal Origin: Australia Boulder Opal
Boulder Opal Treatment: Untreated
Boulder Opal Quantity: 1
Boulder Opal Certificate: GemSelect
Product Description:
View Details
Add to Cart
17.03ct Loose Boulder Opal | 17.03 ct Fancy Boulder Opal, 26.9 x 13.5 mm From Australia, Photo A

17.03 ct Fancy Boulder Opal, 26.9 x 13.5 mm From Australia

Natural Boulder Opal, Qty: 1 pc | 17.03 carat weight Boulder Opal

17.03ct1 Piece
$ 93.67
26.9 x 13.5 mm
Item Description
Stone Type: Loose Boulder Opal
Boulder Opal Weight: 17.03 ct Boulder Opal
Boulder Opal Shape: Fancy Cabochon Boulder Opal
Boulder Opal Size: 26.9 x 13.5 mm Boulder Opal
Boulder Opal Color: Multicolor Boulder Opal
Boulder Opal Clarity: Opaque Boulder Opal
Boulder Opal Origin: Australia Boulder Opal
Boulder Opal Treatment: Untreated
Boulder Opal Quantity: 1
Boulder Opal Certificate: GemSelect
Product Description:
View Details
Add to Cart
25.75ct Loose Boulder Opal | 25.75 ct Fancy Boulder Opal, 21 x 18.4 mm From Australia, Photo A
Click for Product Video (521765)

25.75 ct Fancy Boulder Opal, 21 x 18.4 mm From Australia

Natural Boulder Opal, Qty: 1 pc | 25.75 carat weight Boulder Opal

25.75ct1 Piece
$ 141.63
21 x 18.4 mm
Item Description
Stone Type: Loose Boulder Opal
Boulder Opal Weight: 25.75 ct Boulder Opal
Boulder Opal Shape: Fancy Cabochon Boulder Opal
Boulder Opal Size: 21 x 18.4 mm Boulder Opal
Boulder Opal Color: Multicolor Boulder Opal
Boulder Opal Clarity: Opaque Boulder Opal
Boulder Opal Origin: Australia Boulder Opal
Boulder Opal Treatment: Untreated
Boulder Opal Quantity: 1
Boulder Opal Certificate: GemSelect
Product Description:
View Details
Add to Cart
21.39ct Loose Boulder Opal | 21.39 ct Cushion Boulder Opal, 16.4 x 16.4 mm From Australia, Photo A

21.39 ct Cushion Boulder Opal, 16.4 x 16.4 mm From Australia

Natural Boulder Opal, Qty: 1 pc | 21.39 carat weight Boulder Opal

21.39ct1 Piece
$ 164.70
16.4 x 16.4 mm
Item Description
Stone Type: Loose Boulder Opal
Boulder Opal Weight: 21.39 ct Boulder Opal
Boulder Opal Shape: Cushion Cabochon Boulder Opal
Boulder Opal Size: 16.4 x 16.4 mm Boulder Opal
Boulder Opal Color: Multicolor Boulder Opal
Boulder Opal Clarity: Opaque Boulder Opal
Boulder Opal Origin: Australia Boulder Opal
Boulder Opal Treatment: Untreated
Boulder Opal Quantity: 1
Boulder Opal Certificate: GemSelect
Product Description:
View Details
Add to Cart
22.12ct Loose Boulder Opal | 22.12 ct Oval Boulder Opal, 27.5 x 12.8 mm From Australia, Photo A

22.12 ct Oval Boulder Opal, 27.5 x 12.8 mm From Australia

Natural Boulder Opal, Qty: 1 pc | 22.12 carat weight Boulder Opal

22.12ct1 Piece
$ 154.84
27.5 x 12.8 mm
Item Description
Stone Type: Loose Boulder Opal
Boulder Opal Weight: 22.12 ct Boulder Opal
Boulder Opal Shape: Oval Cabochon Boulder Opal
Boulder Opal Size: 27.5 x 12.8 mm Boulder Opal
Boulder Opal Color: Multicolor Boulder Opal
Boulder Opal Clarity: Opaque Boulder Opal
Boulder Opal Origin: Australia Boulder Opal
Boulder Opal Treatment: Untreated
Boulder Opal Quantity: 1
Boulder Opal Certificate: GemSelect
Product Description:
View Details
Add to Cart
35.99ct Loose Boulder Opal | 35.99 ct Fancy Boulder Opal, 45 x 23.8 mm From Australia, Photo A
Click for Product Video (575226)

35.99 ct Fancy Boulder Opal, 45 x 23.8 mm From Australia

Natural Boulder Opal, Qty: 1 pc | 35.99 carat weight Boulder Opal

35.99ct1 Piece
$ 107.97
45 x 23.8 mm
Item Description
Stone Type: Loose Boulder Opal
Boulder Opal Weight: 35.99 ct Boulder Opal
Boulder Opal Shape: Fancy Cabochon Boulder Opal
Boulder Opal Size: 45 x 23.8 mm Boulder Opal
Boulder Opal Color: Multicolor Boulder Opal
Boulder Opal Clarity: Opaque Boulder Opal
Boulder Opal Origin: Australia Boulder Opal
Boulder Opal Treatment: Untreated
Boulder Opal Quantity: 1
Boulder Opal Certificate: GemSelect
Product Description:
View Details
Add to Cart
8.11ct Loose Boulder Opal | 8.11 carat Pear Boulder Opal, loose Certified Boulder Opal from Australia, Natural Untreated Gem, 22.1 x 13.8 mm, Photo A

8.11 carat Pear Boulder Opal, loose Certified Boulder Opal from Australia, Natural Untreated Gem, 22.1 x 13.8 mm

Natural Boulder Opal, Qty: 1 pc | 8.11 carat weight Boulder Opal

8.11ct1 Piece
$ 90.55
22.1 x 13.8 mm
Item Description
Stone Type: Loose Boulder Opal
Boulder Opal Weight: 8.11 ct Boulder Opal
Boulder Opal Shape: Pear Cabochon Boulder Opal
Boulder Opal Size: 22.1 x 13.8 mm Boulder Opal
Boulder Opal Color: Multicolor Boulder Opal
Boulder Opal Clarity: Opaque Boulder Opal
Boulder Opal Origin: Australia Boulder Opal
Boulder Opal Treatment: Untreated
Boulder Opal Quantity: 1
Boulder Opal Certificate: GemSelect
Product Description:
View Details
Add to Cart
23.38ct Loose Boulder Opal | 23.38 ct Fancy Boulder Opal, 25.3 x 16.7 mm From Australia, Photo A

23.38 ct Fancy Boulder Opal, 25.3 x 16.7 mm From Australia

Natural Boulder Opal, Qty: 1 pc | 23.38 carat weight Boulder Opal

23.38ct1 Piece
$ 116.90
25.3 x 16.7 mm
Item Description
Stone Type: Loose Boulder Opal
Boulder Opal Weight: 23.38 ct Boulder Opal
Boulder Opal Shape: Fancy Cabochon Boulder Opal
Boulder Opal Size: 25.3 x 16.7 mm Boulder Opal
Boulder Opal Color: Multicolor Boulder Opal
Boulder Opal Clarity: Opaque Boulder Opal
Boulder Opal Origin: Australia Boulder Opal
Boulder Opal Treatment: Untreated
Boulder Opal Quantity: 1
Boulder Opal Certificate: GemSelect
Product Description:
View Details
Add to Cart
14.98ct Loose Boulder Opal | 14.98 ct Cushion Boulder Opal, 20.2 x 13.9 mm From Australia, Photo A

14.98 ct Cushion Boulder Opal, 20.2 x 13.9 mm From Australia

Natural Boulder Opal, Qty: 1 pc | 14.98 carat weight Boulder Opal

14.98ct1 Piece
$ 104.86
20.2 x 13.9 mm
Item Description
Stone Type: Loose Boulder Opal
Boulder Opal Weight: 14.98 ct Boulder Opal
Boulder Opal Shape: Cushion Cabochon Boulder Opal
Boulder Opal Size: 20.2 x 13.9 mm Boulder Opal
Boulder Opal Color: Multicolor Boulder Opal
Boulder Opal Clarity: Opaque Boulder Opal
Boulder Opal Origin: Australia Boulder Opal
Boulder Opal Treatment: Untreated
Boulder Opal Quantity: 1
Boulder Opal Certificate: GemSelect
Product Description:
View Details
Add to Cart
20.80ct Loose Boulder Opal | 20.8 ct Fancy Boulder Opal, 32.3 x 16.8 mm From Australia, Photo A

20.8 ct Fancy Boulder Opal, 32.3 x 16.8 mm From Australia

Natural Boulder Opal, Qty: 1 pc | 20.80 carat weight Boulder Opal

20.80ct1 Piece
$ 114.40
32.3 x 16.8 mm
Item Description
Stone Type: Loose Boulder Opal
Boulder Opal Weight: 20.80 ct Boulder Opal
Boulder Opal Shape: Fancy Cabochon Boulder Opal
Boulder Opal Size: 32.3 x 16.8 mm Boulder Opal
Boulder Opal Color: Multicolor Boulder Opal
Boulder Opal Clarity: Opaque Boulder Opal
Boulder Opal Origin: Australia Boulder Opal
Boulder Opal Treatment: Untreated
Boulder Opal Quantity: 1
Boulder Opal Certificate: GemSelect
Product Description:
View Details
Add to Cart
21.82ct Loose Boulder Opal | 21.82 ct Cushion Boulder Opal, 20.7 x 16.1 mm From Australia, Photo A
Click for Product Video (627639)

21.82 ct Cushion Boulder Opal, 20.7 x 16.1 mm From Australia

Natural Boulder Opal, Qty: 1 pc | 21.82 carat weight Boulder Opal

21.82ct1 Piece
$ 168.01
20.7 x 16.1 mm
Item Description
Stone Type: Loose Boulder Opal
Boulder Opal Weight: 21.82 ct Boulder Opal
Boulder Opal Shape: Cushion Cabochon Boulder Opal
Boulder Opal Size: 20.7 x 16.1 mm Boulder Opal
Boulder Opal Color: Multicolor Boulder Opal
Boulder Opal Clarity: Opaque Boulder Opal
Boulder Opal Origin: Australia Boulder Opal
Boulder Opal Treatment: Untreated
Boulder Opal Quantity: 1
Boulder Opal Certificate: GemSelect
Product Description:
View Details
Add to Cart
20.97ct Loose Boulder Opal | 20.97 ct Oval Boulder Opal, 21.5 x 15.7 mm From Australia, Photo A

20.97 ct Oval Boulder Opal, 21.5 x 15.7 mm From Australia

Natural Boulder Opal, Qty: 1 pc | 20.97 carat weight Boulder Opal

20.97ct1 Piece
$ 104.85
21.5 x 15.7 mm
Item Description
Stone Type: Loose Boulder Opal
Boulder Opal Weight: 20.97 ct Boulder Opal
Boulder Opal Shape: Oval Cabochon Boulder Opal
Boulder Opal Size: 21.5 x 15.7 mm Boulder Opal
Boulder Opal Color: Multicolor Boulder Opal
Boulder Opal Clarity: Opaque Boulder Opal
Boulder Opal Origin: Australia Boulder Opal
Boulder Opal Treatment: Untreated
Boulder Opal Quantity: 1
Boulder Opal Certificate: GemSelect
Product Description:
View Details
Add to Cart
25.30ct Loose Boulder Opal | 25.3 ct Oval Boulder Opal, 29.7 x 13.5 mm From Australia, Photo A

25.3 ct Oval Boulder Opal, 29.7 x 13.5 mm From Australia

Natural Boulder Opal, Qty: 1 pc | 25.30 carat weight Boulder Opal

25.30ct1 Piece
$ 177.10
29.7 x 13.5 mm
Item Description
Stone Type: Loose Boulder Opal
Boulder Opal Weight: 25.30 ct Boulder Opal
Boulder Opal Shape: Oval Cabochon Boulder Opal
Boulder Opal Size: 29.7 x 13.5 mm Boulder Opal
Boulder Opal Color: Multicolor Boulder Opal
Boulder Opal Clarity: Opaque Boulder Opal
Boulder Opal Origin: Australia Boulder Opal
Boulder Opal Treatment: Untreated
Boulder Opal Quantity: 1
Boulder Opal Certificate: GemSelect
Product Description:
View Details
Add to Cart
17.73ct Loose Boulder Opal | 17.73 ct Fancy Boulder Opal, 23.7 x 15.3 mm From Australia, Photo A

17.73 ct Fancy Boulder Opal, 23.7 x 15.3 mm From Australia

Natural Boulder Opal, Qty: 1 pc | 17.73 carat weight Boulder Opal

17.73ct1 Piece
$ 88.65
23.7 x 15.3 mm
Item Description
Stone Type: Loose Boulder Opal
Boulder Opal Weight: 17.73 ct Boulder Opal
Boulder Opal Shape: Fancy Cabochon Boulder Opal
Boulder Opal Size: 23.7 x 15.3 mm Boulder Opal
Boulder Opal Color: Multicolor Boulder Opal
Boulder Opal Clarity: Opaque Boulder Opal
Boulder Opal Origin: Australia Boulder Opal
Boulder Opal Treatment: Untreated
Boulder Opal Quantity: 1
Boulder Opal Certificate: GemSelect
Product Description:
View Details
Add to Cart
34.16ct Loose Boulder Opal | 34.16 ct Oval Boulder Opal, 23.4 x 19.6 mm From Australia, Photo A
Click for Product Video (410119)

34.16 ct Oval Boulder Opal, 23.4 x 19.6 mm From Australia

Natural Boulder Opal, Qty: 1 pc | 34.16 carat weight Boulder Opal

34.16ct1 Piece
$ 263.42
23.4 x 19.6 mm
Item Description
Stone Type: Loose Boulder Opal
Boulder Opal Weight: 34.16 ct Boulder Opal
Boulder Opal Shape: Oval Cabochon Boulder Opal
Boulder Opal Size: 23.4 x 19.6 mm Boulder Opal
Boulder Opal Color: Multicolor Boulder Opal
Boulder Opal Clarity: Opaque Boulder Opal
Boulder Opal Origin: Australia Boulder Opal
Boulder Opal Treatment: Untreated
Boulder Opal Quantity: 1
Boulder Opal Certificate: GemSelect
Product Description:
View Details
Add to Cart
12.07ct Loose Boulder Opal | 12.07 ct Oval Boulder Opal, 27.4 x 9.9 mm From Australia, Photo A

12.07 ct Oval Boulder Opal, 27.4 x 9.9 mm From Australia

Natural Boulder Opal, Qty: 1 pc | 12.07 carat weight Boulder Opal

12.07ct1 Piece
$ 84.49
27.4 x 9.9 mm
Item Description
Stone Type: Loose Boulder Opal
Boulder Opal Weight: 12.07 ct Boulder Opal
Boulder Opal Shape: Oval Cabochon Boulder Opal
Boulder Opal Size: 27.4 x 9.9 mm Boulder Opal
Boulder Opal Color: Multicolor Boulder Opal
Boulder Opal Clarity: Opaque Boulder Opal
Boulder Opal Origin: Australia Boulder Opal
Boulder Opal Treatment: Untreated
Boulder Opal Quantity: 1
Boulder Opal Certificate: GemSelect
Product Description:
View Details
Add to Cart
41.37ct Loose Boulder Opal | 41.37 ct Oval Boulder Opal, 29.7 x 21.2 mm From Australia, Photo A
Click for Product Video (522985)

41.37 ct Oval Boulder Opal, 29.7 x 21.2 mm From Australia

Natural Boulder Opal, Qty: 1 pc | 41.37 carat weight Boulder Opal

41.37ct1 Piece
$ 227.54
29.7 x 21.2 mm
Item Description
Stone Type: Loose Boulder Opal
Boulder Opal Weight: 41.37 ct Boulder Opal
Boulder Opal Shape: Oval Cabochon Boulder Opal
Boulder Opal Size: 29.7 x 21.2 mm Boulder Opal
Boulder Opal Color: Multicolor Boulder Opal
Boulder Opal Clarity: Opaque Boulder Opal
Boulder Opal Origin: Australia Boulder Opal
Boulder Opal Treatment: Untreated
Boulder Opal Quantity: 1
Boulder Opal Certificate: GemSelect
Product Description:
View Details
Add to Cart
20.10ct Loose Boulder Opal | 20.1 ct Cushion Boulder Opal, 21.1 x 16.6 mm From Australia, Photo A

20.1 ct Cushion Boulder Opal, 21.1 x 16.6 mm From Australia

Natural Boulder Opal, Qty: 1 pc | 20.10 carat weight Boulder Opal

20.10ct1 Piece
$ 100.50
21.1 x 16.6 mm
Item Description
Stone Type: Loose Boulder Opal
Boulder Opal Weight: 20.10 ct Boulder Opal
Boulder Opal Shape: Cushion Cabochon Boulder Opal
Boulder Opal Size: 21.1 x 16.6 mm Boulder Opal
Boulder Opal Color: Multicolor Boulder Opal
Boulder Opal Clarity: Opaque Boulder Opal
Boulder Opal Origin: Australia Boulder Opal
Boulder Opal Treatment: Untreated
Boulder Opal Quantity: 1
Boulder Opal Certificate: GemSelect
Product Description:
View Details
Add to Cart
26.43ct Loose Boulder Opal | 26.43 ct Oval Boulder Opal, 28.5 x 17.9 mm From Australia, Photo A
Click for Product Video (521759)

26.43 ct Oval Boulder Opal, 28.5 x 17.9 mm From Australia

Natural Boulder Opal, Qty: 1 pc | 26.43 carat weight Boulder Opal

26.43ct1 Piece
$ 145.37
28.5 x 17.9 mm
Item Description
Stone Type: Loose Boulder Opal
Boulder Opal Weight: 26.43 ct Boulder Opal
Boulder Opal Shape: Oval Cabochon Boulder Opal
Boulder Opal Size: 28.5 x 17.9 mm Boulder Opal
Boulder Opal Color: Multicolor Boulder Opal
Boulder Opal Clarity: Opaque Boulder Opal
Boulder Opal Origin: Australia Boulder Opal
Boulder Opal Treatment: Untreated
Boulder Opal Quantity: 1
Boulder Opal Certificate: GemSelect
Product Description:
View Details
Add to Cart
16.81ct Loose Boulder Opal | 16.81 ct Fancy Boulder Opal, 28.8 x 13.1 mm From Australia, Photo A
Click for Product Video (628411)

16.81 ct Fancy Boulder Opal, 28.8 x 13.1 mm From Australia

Natural Boulder Opal, Qty: 1 pc | 16.81 carat weight Boulder Opal

16.81ct1 Piece
$ 84.05
28.8 x 13.1 mm
Item Description
Stone Type: Loose Boulder Opal
Boulder Opal Weight: 16.81 ct Boulder Opal
Boulder Opal Shape: Fancy Cabochon Boulder Opal
Boulder Opal Size: 28.8 x 13.1 mm Boulder Opal
Boulder Opal Color: Multicolor Boulder Opal
Boulder Opal Clarity: Opaque Boulder Opal
Boulder Opal Origin: Australia Boulder Opal
Boulder Opal Treatment: Untreated
Boulder Opal Quantity: 1
Boulder Opal Certificate: GemSelect
Product Description:
View Details
Add to Cart
20.30ct Loose Boulder Opal | 20.3 ct Fancy Boulder Opal, 25.5 x 16 mm From Australia, Photo A

20.3 ct Fancy Boulder Opal, 25.5 x 16 mm From Australia

Natural Boulder Opal, Qty: 1 pc | 20.30 carat weight Boulder Opal

20.30ct1 Piece
$ 101.50
25.5 x 16 mm
Item Description
Stone Type: Loose Boulder Opal
Boulder Opal Weight: 20.30 ct Boulder Opal
Boulder Opal Shape: Fancy Cabochon Boulder Opal
Boulder Opal Size: 25.5 x 16 mm Boulder Opal
Boulder Opal Color: Multicolor Boulder Opal
Boulder Opal Clarity: Opaque Boulder Opal
Boulder Opal Origin: Australia Boulder Opal
Boulder Opal Treatment: Untreated
Boulder Opal Quantity: 1
Boulder Opal Certificate: GemSelect
Product Description:
View Details
Add to Cart
21.59ct Loose Boulder Opal | 21.59 ct Fancy Boulder Opal, 24.1 x 18.3 mm From Australia, Photo A

21.59 ct Fancy Boulder Opal, 24.1 x 18.3 mm From Australia

Natural Boulder Opal, Qty: 1 pc | 21.59 carat weight Boulder Opal

21.59ct1 Piece
$ 107.95
24.1 x 18.3 mm
Item Description
Stone Type: Loose Boulder Opal
Boulder Opal Weight: 21.59 ct Boulder Opal
Boulder Opal Shape: Fancy Cabochon Boulder Opal
Boulder Opal Size: 24.1 x 18.3 mm Boulder Opal
Boulder Opal Color: Multicolor Boulder Opal
Boulder Opal Clarity: Opaque Boulder Opal
Boulder Opal Origin: Australia Boulder Opal
Boulder Opal Treatment: Untreated
Boulder Opal Quantity: 1
Boulder Opal Certificate: GemSelect
Product Description:
View Details
Add to Cart
17.29ct Loose Boulder Opal | 17.29 ct Fancy Boulder Opal, 27 x 17.2 mm From Australia, Photo A

17.29 ct Fancy Boulder Opal, 27 x 17.2 mm From Australia

Natural Boulder Opal, Qty: 1 pc | 17.29 carat weight Boulder Opal

17.29ct1 Piece
$ 95.10
27 x 17.2 mm
Item Description
Stone Type: Loose Boulder Opal
Boulder Opal Weight: 17.29 ct Boulder Opal
Boulder Opal Shape: Fancy Cabochon Boulder Opal
Boulder Opal Size: 27 x 17.2 mm Boulder Opal
Boulder Opal Color: Multicolor Boulder Opal
Boulder Opal Clarity: Opaque Boulder Opal
Boulder Opal Origin: Australia Boulder Opal
Boulder Opal Treatment: Untreated
Boulder Opal Quantity: 1
Boulder Opal Certificate: GemSelect
Product Description:
View Details
Add to Cart
1 2 3
1 - 7

Opals really are a mixed bag of gemstones. Just some of the varieties include white opals, black opals, fire opals, pink Peruvian opals, hyalite opals and I could go on for quite a while yet.

Boulder Opals are one of the better known gemstones in this family. They are distinct from most other opals by still being connected to the rock in which they formed.

This means that the thin slivers of precious opal have a substantial foundation so it is much more durable and the dark rock is a perfect background for the vibrant play-of-color.

Boulder Opal Colors

There is no such thing as a typical Boulder Opal color. Every gemstone is different in both shape and color with every color of the rainbow a possibility. Not only can Boulder Opals feature all colors but as the stone moves other colors can flash or dance before your eyes.

The precious opal material that forms in cracks and crevices within the host rock is made up of tiny spheres in which light can bounce around creating the dazzling colors.

Larger spheres bring out the red colors while smaller spheres show up as blue. Large spheres are rarer so any Boulder Opal showing colors such as red or orange - the ones at the top of the rainbow - will be more expensive than the blues and greens found at the bottom.

Read more about gemstones colors here

Boulder Opal Species

Boulder Opals are just one of many types of opals found around the world. Some have the famous play-of-color while others are a single color but all are fascinating gemstones.

Just a few of the more well-known ones are:

And there are many more besides.

Boulder Opal Price

Like most gemstones, it is the color of the Boulder Opal that is the number one consideration when appraising its price. However, there are a couple of extra considerations to bear in mind with this stone.

There is the coverage - a gemstone that has a large area of precious opal spread over the surface will get a higher price than one with a few spots here and there.

A contrast between a dark background and a bright color can increase the value of the opal.

As we mentioned earlier, some colors are rarer than others and a simple rule is to work your way down the rainbow with the red at the top being the most expensive and the purple at the bottom being the least expensive.

This is a very basic rule which can vary from stone to stone with the coverage and contrast aspects to bear in mind.

Carat Weight

Boulder Opals are precious opal material still connected to the base rock so they tend to be quite large gemstones. They can also be irregular shapes to incorporate as much of the naturally occurring opal as possible.

Pricing Boulder Opals on carat weight can be a little tricky as there is often a lot of ironstone or sandstone left after cutting and polishing. It may be a very thick and heavy stone with just a thin veneer of colored opal on the front.

It is best to choose your Boulder Opal based on physical size - the length, width and height - rather than carat size. As a very rough guide, Boulder Opals can be anything from $2 to $15 per carat for basic colors up to $50 to $800 per carat for gemstones with outstanding colors, depending on color, coverage and contrast.

Treatments

Generally, Boulder Opals are a completely natural gemstone with no treatment other than cutting and polishing.

As we have said, the contrast between the opal and the rock background can increase the value so there have been cases of the base rock being smoked or soaked in sugar to darken up the body but this is not very common in Boulder Opals and happens more with Black Opals.

Sometimes the precious opal can come loose from the rock backing and can be reattached with glue or resin. This would be difficult to spot unless a sudden impact or high heat breaks the seal but we are not aware of this being a serious problem.

Any treatment received by any of our gemstones is clearly disclosed.

Where are Boulder Opals found?

Basically all Boulder Opals come from central Queensland. This may not sound that impressive but it is an area about the size of California and home to about 200,000 people (and lots of kangaroos, rock wallabies, goannas and spiders).

What jewelry is Boulder Opal suitable for?

Boulder Opals have a rating of 5.5 to 6.5 on Mohs hardness scale. This would usually make them a little bit fragile for many jewelry items and not suitable for daily wear, however Boulder Opals are still attached to the durable rocks they formed in so are much tougher than the rating would suggest.

Large and striking Boulder Opals cut into interesting odd shapes can help create wonderful and unique jewelry items, especially pendants, brooches and earrings where durability is not such an issue. Boulder opal rings in protective settings can be particularly striking items of jewelry.

Birthstones and Anniversaries

Boulder Opals are the birthstone of October and would make an ideal gift for anyone celebrating a birthday in that month.

A Boulder Opal is the traditional gemstone gift for the 14th wedding anniversary.

Read All

Over 19 Years in the Gemstone Business!

Thank you for trusting us with your purchase!

Overall Rating -> 10 star ratings

I have received emails for about a year and today is the condition that had me decide on the purchase

Posted By Tim in April, 2024
Source: Bizrate

Overall Rating -> 10 star ratings

Love gemselect

Posted By Joshua Howard in March, 2024
Source: Bizrate

Overall Rating -> 10 star ratings

Easy to use.

Posted By Hope in March, 2024
Source: Bizrate

Overall Rating -> 10 star ratings

Very pleased with shopping on this site. It's easy to navigate and information about gemstones is very good.

Posted By Kate in December, 2023
Source: Bizrate

Overall Rating -> 9 star ratings

I am of the opinion that the company gem select cares about the product beautiful gems it sells and the cost of the gem I purchased was small i was treated as if it cost a lot of money and product was described in detail and i felt good about the little stones i had ordered.

Posted By Sparkle in March, 2024
Source: Bizrate

Overall Rating -> 10 star ratings

I really enjoy browsing through GemSelect. The selection is always marvelous and I love how detailed everything is described. The only thing I noticed is that when browsing through my phone, the videos of the gems do not load. If there were more videos of the gems, that would be amazing, though I understand that is a lot of work on GemSelect's part! Checking out is also very fast and easy, and I love that the return policy is very good, though I hope I don't have to use it anytime soon.

Posted By ChiChi in January, 2024
Source: Bizrate

Overall Rating -> 9 star ratings

I was in the market for birthstones for a lil gift project im doing. I'm no expert in gems or what not but the quality as far as i can tell seems to be spot on.

Posted By PixelComposer in January, 2024
Source: Bizrate

Overall Rating -> 10 star ratings

Easy to find products I want. I've ordered several times from gem select and never any problems. Will order again. Thank you.

Posted By Ray in January, 2024
Source: Bizrate

Overall Rating -> 9 star ratings

So many gorgeous stones! The only "complaint" I have is it's difficult to visualize sizes in mm. Perhaps some way to compare in inches?It has been a long time since I bought stones from Gem select, but the process wasn't too difficult.

Posted By Ktreva52 in February, 2024
Source: Bizrate

Overall Rating -> 10 star ratings

I really enjoy browsing through GemSelect. The selection is always marvelous and I love how detailed everything is described. The only thing I noticed is that when browsing through my phone, the videos of the gems do not load. If there were more videos of the gems, that would be amazing, though I understand that is a lot of work on GemSelect's part! Checking out is also very fast and easy, and I love that the return policy is very good, though I hope I don't have to use it anytime soon.

Posted By ChiChi in January, 2024
Source: Bizrate

Overall Rating -> 10 star ratings

i love this site, the gems are always of good quality, i've been buy gifts from the site for 10 years, love it

Posted By Jf in January, 2024
Source: Bizrate

Overall Rating -> 10 star ratings

No issues at all. It was great.

Posted By LJXK in May, 2023
Source: Bizrate

Overall Rating -> 9 star ratings

It was simple and clear to understand.

Posted By Thora007 in December, 2023
Source: Bizrate

Overall Rating -> 9 star ratings

Never bought anything on this website before, but it probably won't be my last purchase. Definitely one of the easiest to use and most informative sites I've ever been to.

Posted By Bob in November, 2023
Source: Bizrate

Overall Rating -> 9 star ratings

Good interaction with site

Posted By Brick in September, 2023
Source: Bizrate

Overall Rating -> 10 star ratings

Overall, the whole process was just great.

Posted By Thatoneguy in August, 2023
Source: Bizrate

Overall Rating -> 10 star ratings

The gem stone always has a great selection of beautiful stones. The calibrated stone fit my ring perfectly. Thank you gem select !

Posted By Jen in August, 2023
Source: Bizrate

Overall Rating -> 9 star ratings

It's a nice site with good pictures and products

Posted By Online Shopper in July, 2023
Source: Bizrate

Overall Rating -> 10 star ratings

I enjoyed browsing though different varieties of rubies. I felt that the experience was simple and easy to navigate!

Posted By Daws in July, 2023
Source: Bizrate

Overall Rating -> 8 star ratings

Great interaction!

Posted By Online Shopper in April, 2023
Source: Bizrate

Overall Rating -> 10 star ratings

I was able to find exactly what I wanted.

Posted By Online Shopper in April, 2023
Source: Bizrate
STAY IN TOUCH | NEWSLETTER
*You're signing up to receive GemSelect promotional email.
Partners and Trust Payment options

Switch to Mobile Version

Copyright © 2005-2024 GemSelect.com all rights reserved.

Reproduction (text or graphics) without the express written consent of GemSelect.com (SETT Company Ltd.) is strictly prohibited.

1088

Continue Shopping
Checkout
Continue Shopping
Checkout