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Buy 12 Carat Gems

(984)
Gem Type Weight Size Clarity Price Origin
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Multicolor Rhodochrosite Gem - 11.6ct Oval Cabochon (ID: 546213)

Oval Multicolor Rhodochrosite

11.6ct
20.7 x 12.9 mm
$ 9.24
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Multicolor Quartz With Marcasite Gem - 11.6ct Oval Cabochon (ID: 522415)

Oval Multicolor Quartz With Marcasite

11.6ct
18.5 x 12.3 mm
$ 69.36
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Medium Brown Smoky Quartz Gem - 11.6ct Octagon / Scissor Cut (ID: 408264)

Octagon / Emerald Cut Brown Smoky Quartz

11.6ct
14.2 x 14.2 mm
$ 20.84
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Golden Yellow Star Sapphire Gem - 12.4ct Oval Cabochon (ID: 522547)

Oval Golden Star Sapphire

12.4ct
15.3 x 12.6 mm
$ 111.69
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Multicolor Spectrolite Gem - 12.3ct Pear Cabochon (ID: 513069)

Pear Multicolor Spectrolite

12.3ct
24 x 15.2 mm
$ 40.35
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Multicolor Ruby in Fuchsite Gem - 12ct Marquise Slice (ID: 384798)

Marquise Multicolor Ruby in Fuchsite

12ct
28.6 x 15.5 mm
$ 82.10
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Bright Blue Color-Change Fluorite Gem - 12.6ct Round Facet (ID: 413734)

Round Blue Color-Change Fluorite

12.6ct
15 mm
$ 316.00
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Navy Blue Lapis Lazuli Gem - 11.6ct Oval Cabochon (ID: 523873)

Oval Blue Lapis Lazuli

11.6ct
15.2 x 11.1 mm
$ 17.39
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Medium-Dark Golden Citrine Gem - 12.6ct Octagon Step Cut (ID: 500716)

Octagon / Emerald Cut Golden Citrine

12.6ct
16.1 x 12 mm
$ 73.96
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Click for Product Video (462221)
Multicolor Opal Gem - 12.1ct Trillion Cabochon (ID: 462221)

Trillion Multicolor Opal

12.1ct
18 x 17.2 mm
$ 485.54
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2 pcs
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Multicolor Tiger's Eye Matrix Gem - 12.4ct Drilled Sphere (ID: 422971)

Sphere / Ball Multicolor Tiger's Eye Matrix

12.42 ct (total 24.84ctw)
12 mm
$ 19.87
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Medium Brown Smoky Quartz Gem - 12.2ct Octagon / Scissor Cut (ID: 514349)

Octagon / Emerald Cut Brown Smoky Quartz

12.2ct
14.2 x 14.2 mm
$ 20.72
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Lime Green Prehnite Gem - 12.8ct Carved Fruit (ID: 418421)

Fancy Green Prehnite

12.8ct
19.3 x 12.2 mm
$ 19.17
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2 pcs
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Multicolor Agate Geode Gem - 12.1ct Fancy Crystal Cluster (ID: 455299)

Fancy Multicolor Agate Geode

12.10 ct (total 24.20ctw)
23.3 x 16 mm
$ 48.40
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Multicolor Coral Gem - 11.8ct Oval Cabochon (ID: 494699)

Oval Multicolor Coral

11.8ct
22.2 x 12.9 mm
$ 33.45
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2 pcs
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Multicolor Jasper Gem - 13ct Drilled Sphere (ID: 361815)

Sphere / Ball Multicolor Jasper

12.97 ct (total 25.94ctw)
12.3 mm
$ 25.94
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Multicolor Jasper Gem - 11.9ct Oval Cabochon (ID: 364126)

Oval Multicolor Jasper

11.9ct
22.2 x 16.3 mm
$ 23.76
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Multicolor Rhodochrosite Gem - 12.7ct Pear Cabochon (ID: 503495)

Pear Multicolor Rhodochrosite

12.74 ct (total 25.48ctw)
24.3 x 10.6 mm
$ 19.11
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Bright Gold Citrine Gem - 11.6ct Oval Facet (ID: 504828)

Oval Golden Citrine

11.6ct
18.1 x 13 mm
$ 81.34
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Multicolor Ruby-Zoisite Gem - 12.2ct Baguette Cabochon (ID: 338113)

Baguette Multicolor Ruby-Zoisite

12.2ct
14.3 x 11.2 mm
$ 30.60
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Medium Red Strawberry Quartz Gem - 12.8ct Oval Facet (ID: 471620)

Oval Red Strawberry Quartz

12.8ct
15.7 x 12.8 mm
$ 89.60
Item in Stock
12 Carat Gems
Buy gems by weight. Select the best 12 carat gems from a wide array of colored stones, including rare gem types such as scapolite, black opal and pietersite. Also available are beautiful and popular faceted gems, including tanzanite, zircon and tourmaline. Large 12-carat gems make perfect statement stones, whether they are worn as a necklace pendant, ring or another jewelry design. Browse the largest selection of natural loose colored gemstones available in 12 carats. From here, you can use our filters at the top or on the left-hand side to find gems by gem type, color, shape, cut and so on. For example, select 'jadeite' to see all of our 12-carat jadeite gems. Select 'green' to shop for 12-carat green gems. You can also filter by single, pairs, lots, faceted gems or cabochons by using the check boxes at the top.
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More Shapes
  • Asscher Cut
  • Baguette / Scissor Cut
  • Baguette Cabochon
  • Baguette Checkerboard
  • Baguette Crystal Cluster
  • Baguette Facet
  • Baguette Rose-Cut
  • Baguette Step Cut
  • Baguette Sugarloaf Cabochon
  • Baroque
  • Barrel
  • Barrel / Checkerboard
  • Barrel / Full-Round
  • Barrel / Scissor Cut
  • Barrel Cabochon
  • Barrel Rose Cut
  • Bear Carving with Hole
  • Bird Carving
  • Briolette
  • Briolette with Hole
  • Carved Baguette
  • Carved Cameo
  • Carved Cushion
  • Carved Elephant
  • Carved Fancy
  • Carved Fish
  • Carved Fish with Hole
  • Carved Flower
  • Carved Fruit
  • Carved Half Heart
  • Carved Half Moon
  • Carved Heart
  • Carved Heart Cabochon
  • Carved Leaf
  • Carved Marquise
  • Carved Marquise Cabochon
  • Carved Octagon
  • Carved Oval
  • Carved Oval Cabochon
  • Carved Owl
  • Carved Pear
  • Carved Pear Cabochon
  • Carved Rhomb
  • Carved Rose
  • Carved Rose with Half Drilled Hole
  • Carved Round
  • Carved Round Bar
  • Carved Round Cabochon
  • Carved Sheep
  • Carved Shell
  • Carved Square
  • Carved Teardrop
  • Carved Trillion
  • Carved Turtle
  • Cushion Buff-Top
  • Cushion Cabochon
  • Cushion Carved Medusa Cameo
  • Cushion Checkerboard
  • Cushion Checkerboard (double sided)
  • Cushion Concave Fantasy Cut
  • Cushion Crystal Cluster
  • Cushion Rose-Cut
  • Cushion Shape Sugarloaf Cabochon
  • Cushion Sugarloaf Cabochon
  • Cushion-Cut
  • Diamond-Cut
  • Drilled Faceted Sphere
  • Drilled Sphere
  • Drilled Square Rondelle Slice
  • Fancy Cabochon
  • Fancy Carved Cushion
  • Fancy Carved Oval
  • Fancy Carved Pear
  • Fancy Carved Round
  • Fancy Carved Trillion
  • Fancy Carving
  • Fancy Crystal Cluster
  • Fancy Facet
  • Fancy Fantasy Carved Leaf
  • Fancy Fantasy Carving
  • Fancy Slice
  • Fancy Star Facet
  • Fancy-Cut
  • Fantasy Carved Flower
  • Fantasy Carved Flower Cut
  • Fantasy Carved Leaf
  • Flower Carving
  • Flower-Cut
  • Half Heart Cabochon
  • Half Heart Facet
  • Half Moon Cabochon
  • Half Moon Facet-Cut
  • Half Moon Faceted
  • Half-Drilled Briolette
  • Half-Drilled Sphere
  • Heart Cabochon
  • Heart Checkerboard (double sided)
  • Heart Facet
  • Heart Rose-Cut
  • Hexagon Cut
  • Marquise Buff-Top
  • Marquise Cabochon
  • Marquise Checkerboard
  • Marquise Checkerboard (double sided)
  • Marquise Facet
  • Marquise Mixed Cut
  • Marquise Slice
  • Marquise Sugarloaf Cabochon
  • Octagon / Scissor Cut
  • Octagon Cabochon
  • Octagon Checkerboard
  • Octagon Facet
  • Octagon Step Cut
  • Oval Buff-Top
  • Oval Cabochon
  • Oval Cabochon with Hole
  • Oval Carved Cameo
  • Oval Checkerboard
  • Oval Checkerboard (double sided)
  • Oval Concave Cut
  • Oval Crystal Cluster
  • Oval Diamond-Cut
  • Oval Facet
  • Oval Fancy Facet
  • Oval Fantasy Concave Cut
  • Oval Mixed Cut
  • Oval Portuguese-Cut
  • Oval Rose-Cut
  • Oval Slice
  • Pear Cabochon
  • Pear Checkerboard
  • Pear Checkerboard with Hole
  • Pear Concave Cut
  • Pear Concave Fantasy Cut
  • Pear Crystal Cluster
  • Pear Double-Sided Checkerboard
  • Pear Facet
  • Pear Shape Sugarloaf Cabochon
  • Pear Slice
  • Pencil
  • Pencil Cut
  • Princess-Cut
  • Rhomb Cabochon
  • Rhomb Checkerboard
  • Rhomb Checkerboard (Double-Sided)
  • Rhomb Facet
  • Rondelle
  • Round Buff-Top
  • Round Cabochon
  • Round Checkerboard
  • Round Checkerboard (double sided)
  • Round Concave Cut
  • Round Concave Fantasy Cut
  • Round Drilled Checkerboard (Double Sided)
  • Round Drilled Rondelle
  • Round Facet
  • Round Mixed-Cut
  • Round Petal Cut
  • Round Portuguese-Cut
  • Round Rose-Cut
  • Round Rose-Cut (double sided)
  • Round Slice
  • Shark Fin Cabochon
  • Shield Cabochon
  • Spherical
  • Square / Scissor Cut
  • Square Cabochon
  • Square Facet
  • Square Rose-Cut
  • Square Step-Cut
  • Square Sugarloaf Cabochon
  • Square with Hole
  • Tapered Baguette
  • Tapered Baguette Cabochon
  • Teardrop Cabochon
  • Trapezoid
  • Trapezoid Cabochon
  • Trapezoid Checkerboard
  • Triangle
  • Triangle Cabochon
  • Trillion Cabochon
  • Trillion Checkerboard
  • Trillion Concave Cut
  • Trillion Concave Fantasy Cut
  • Trillion Crystal Cluster
  • Trillion Facet
  • Trillion Rose-Cut
  • Trillion Shape Sugarloaf Cabochon
  • Undrilled Briolette Teardrop
Popular Gemstones
  • Sapphire
  • Emerald
  • Ruby
  • Aquamarine
  • Zircon
  • Opal
  • Topaz
  • Tourmaline
  • Garnet
  • Amethyst
  • Citrine
  • Tanzanite
All Gemstones (144)
A B C D E F G H I J K L M N O P Q R S T V Z
  • Actinolite Cat's Eye
  • Agate
  • Agate Geode
  • Almandine Garnet
  • Amazonite
  • Amethyst
  • Ametrine
  • Ammolite
  • Andalusite
  • Andesine Labradorite
  • Apatite
  • Aquamarine
  • Aventurine
  • Beryl
  • Black Opal
  • Bloodstone
  • Boulder Opal
  • Calcite
  • Carnelian
  • Cat's Eye Apatite
  • Cat's Eye Aquamarine
  • Cat's Eye Augite
  • Cat's Eye Gemstones
  • Cat's Eye Moonstone
  • Cat's Eye Opal
  • Cat's Eye Scapolite
  • Chalcedony
  • Charoite
  • Chocolate Opal
  • Chrome Diopside
  • Chrome Tourmaline
  • Chrysoberyl
  • Chrysocolla
  • Chrysoprase
  • Citrine
  • Clinohumite
  • Color-Change Diaspore
  • Color-Change Fluorite
  • Color-Change Garnet
  • Color-Change Sapphire
  • Coral
  • Demantoid Garnet
  • Dendritic Agate
  • Diamond
  • Druzy Amethyst
  • Druzy Azurite
  • Emerald
  • Enstatite
  • Fire Agate
  • Fire Opal
  • Fluorite
  • Fossil Coral
  • Garnet
  • Golden Beryl
  • Grandidierite
  • Grossularite Garnet
  • Hawk's Eye
  • Hematite
  • Hemimorphite Druzy
  • Hessonite Garnet
  • Hiddenite
  • Howlite
  • Idocrase
  • Imperial Topaz
  • Iolite
  • Jade Gemstones
  • Jadeite
  • Jasper
  • Kornerupine
  • Kunzite
  • Kyanite
  • Labradorite
  • Lapis Lazuli
  • Larimar
  • Malachite
  • Malaya Garnet
  • Mali Garnet
  • Maw-Sit-Sit
  • Moonstone
  • Morganite
  • Moss Opal
  • Mother of Pearl
  • Mystic Quartz
  • Mystic Topaz
  • Nuummite
  • Obsidian
  • Opal
  • Opal Doublet
  • Opal in Matrix
  • Pearl
  • Peridot
  • Pietersite
  • Prehnite
  • Pyrite
  • Pyrope Garnet
  • Quartz
  • Quartz Cat's Eye
  • Quartz With Marcasite
  • Rainbow Moonstone
  • Rainbow Pyrite
  • Rhodochrosite
  • Rhodolite Garnet
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  • Rubellite Tourmaline
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  • Ruby-Zoisite
  • Rutile Quartz
  • Sapphire
  • Scolecite
  • Seraphinite
  • Serpentine
  • Sillimanite
  • Sillimanite Cat's Eye
  • Smithsonite
  • Smoky Quartz
  • Snowflake Obsidian
  • Sodalite
  • Spectrolite
  • Spessartite Garnet
  • Sphalerite
  • Sphene
  • Spinel
  • Star Diopside
  • Star Garnet
  • Star Gemstones
  • Star Lemon Quartz
  • Star Moonstone
  • Star Rose Quartz
  • Star Ruby
  • Star Sapphire
  • Star Sunstone
  • Strawberry Quartz
  • Sugilite
  • Sunstone
  • Tanzanite
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Size and Weight

Gems are always measured in Millimeter (mm)

Dimensions are given as;
length x width x depth,
except for round stones which are;
diameter x depth

Select gems by size, not by weight!
Gem varieties vary in density, so carat weight is not a good indication of size

Note: 1ct = 0.2g

Size Comparison Chart