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Buy 18 Carat Gems

(429)
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18 Carat Gems

Buy gems by weight. Shop from our extensive range of beautiful, natural 18-carat gems. Browse the largest selection of natural loose colored gemstones available in 18 carats. Our large gemstone selection includes many popular gem types, such as amethyst, citrine, topaz and turquoise, and lesser-known gems, including ammolite, cat's eye aquamarine and maw-sit-sit. Large, natural 18-carat gems are perfect for making statement jewelry, such as oversized pendants and rings. 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 'moonstone' to see all of our 18-carat moonstone gems. Select 'pink' to shop for 18-carat pink gems. You can also filter by single, pairs, lots, faceted gems or cabochons by using the check boxes at the top.
Certified Customer Reviews
Overall Rating -> 9 star ratings
O.K. experience. Pictures could be a little better, offer more views, especially full face on, to get a better idea of how a stone would look mounted in a ring, i.e., how centered the star is. The prices seem pretty fair.
Posted By CPA in April, 2021
Source: Bizrate
Overall Rating -> 10 star ratings
The selection of gems they had are great and the prices are fair. It is easy to purchase.
Posted By Mmorric in March, 2021
Source: Bizrate
Overall Rating -> 10 star ratings
Gemselect has good prices and many different varieties. I like to collect untreated natural loose gemstones and this is the only website I purchase from. All gemstones are highly detailed about information, state whether they are treated or not, county of origin. I highly recommend them.
Posted By Jake in January, 2021
Source: Bizrate
Overall Rating -> 10 star ratings
It is easy to find everything because its labeled kinda overwhelming but if you know what you are looking for its fine.
Posted By Maahghudah Design in December, 2020
Source: Bizrate
Overall Rating -> 10 star ratings
Well fell in love with the site right away ordered two many items I knew I would return a few. Decided I wanted to invest in a sapphire emerald or ruby after more research. The diamonds that I received we just stuck together just ordered one more I will have 10 in all diamonds two yellow six white. I'm so very happy I didn't know what I was going to keep and definitely diamonds were winner.
Posted By Kaitlin m in April, 2021
Source: Bizrate
Overall Rating -> 9 star ratings
buy a few items every year. Site is easy to use and selection is virtually unlimited. Easy to use and, tho I have no real basis for comparison, prices seem reasonable.
Posted By Jim in March, 2021
Source: Bizrate
Overall Rating -> 9 star ratings
I really am pleased with Gem Select! I have found that most jewelry stores sell lab created stones and I prefer earth stones. Then I have the pleasure of designing my own jewelry to suit me personally! I highly recommend this site1
Posted By Jan in December, 2020
Source: Bizrate
Overall Rating -> 10 star ratings
thank you for everything
Posted By Zafir in December, 2020
Source: Bizrate
Overall Rating -> 10 star ratings
I love GemSelect because they have a super wide range of gems and it is easy to sort them by price to find the one I want!
Posted By Ben in January, 2021
Source: Bizrate
Overall Rating -> 10 star ratings
I wanted an affordable piece of lapis lazuli, and I had so many options. I picked my favorite cut and checkout was super easy!
Posted By Cowan in October, 2020
Source: Bizrate
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Article Categories

Total Number of Articles: 1863

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
  • Ball Facet
  • Baroque
  • Barrel
  • Barrel / Checkerboard
  • Barrel / Full-Round
  • Barrel Cabochon
  • Barrel Checkerboard
  • Barrel Rose Cut
  • Bear Carving with Hole
  • Bird Carving
  • Briolette
  • Briolette with Hole
  • Bullet Shape Checkerboard
  • Carved
  • Carved Bird
  • Carved Cameo
  • Carved Cushion
  • Carved Elephant
  • Carved Fancy
  • Carved Fish
  • Carved Fish with Hole
  • Carved Flower
  • Carved Frog
  • Carved Fruit
  • Carved Half Heart
  • Carved Heart
  • Carved Heart Cabochon
  • Carved Leaf
  • Carved Marquise
  • Carved Marquise Cabochon
  • Carved Octagon
  • Carved Oval
  • Carved Oval Cabochon
  • Carved Pear
  • Carved Pear Cabochon
  • Carved Rhomb
  • Carved Rose
  • Carved Rose with Half Drilled Hole
  • Carved Round
  • Carved Round Bar
  • Carved Round Cabochon
  • 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 Mixed Cut
  • Cushion Rose-Cut
  • Cushion Shape Sugarloaf Cabochon
  • Cushion Sugarloaf Cabochon
  • Cushion-Cut
  • Diamond-Cut
  • Drilled Cube
  • Drilled Faceted Sphere
  • Drilled Sphere
  • Drilled Square Rondelle
  • Drilled Square Rondelle Slice
  • Fancy Bicone
  • Fancy Cabochon
  • Fancy Carved Cushion
  • Fancy Carved Oval
  • Fancy Carved Pear
  • Fancy Carved Round
  • Fancy Carved Trillion
  • Fancy Carving
  • Fancy Crystal Cluster
  • Fancy Cut
  • Fancy Facet
  • Fancy Fantasy Carving
  • Fancy Slice
  • Fancy-Cut
  • Fantasy Carved Flower
  • Fantasy Carved Flower Cut
  • Fantasy Carved Leaf
  • Flower Carving
  • Flower-Cut
  • Half Cylinder Cabochon
  • Half Heart Cabochon
  • Half Heart Facet
  • Half Moon Cabochon
  • Half Moon Facet-Cut
  • Half Moon Faceted
  • Half-Drilled Briolette
  • Half-Drilled Half Cylinder Cabochon
  • Half-Drilled Heart Checkerboard (double sided
  • Half-Drilled Heart Facet
  • Half-Drilled Sphere
  • Heart Buff-Top
  • Heart Cabochon
  • Heart Checkerboard
  • Heart Checkerboard (double sided)
  • Heart Facet
  • Heart Rose-Cut
  • Hexagon Cut
  • Marquise Buff-Top
  • Marquise Cabochon
  • Marquise Checkerboard
  • Marquise Checkerboard (double sided)
  • Marquise Concave Cut
  • Marquise Facet
  • Marquise Mixed Cut
  • Marquise Slice
  • Marquise Sugarloaf Cabochon
  • Octagon / Scissor Cut
  • Octagon Buff-Top
  • Octagon Cabochon
  • Octagon Checkerboard
  • Octagon Concave Cut
  • Octagon Facet
  • Octagon Step Cut
  • Oval Bar 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 Rose-Cut (double sided)
  • 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 Carved Cameo
  • 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 Rose-Cut
  • Round Rose-Cut (double sided)
  • Round Slice
  • Shark Fin Cabochon
  • Shield Cabochon
  • Shield Faceted
  • Spherical
  • Square / Scissor Cut
  • Square Buff-Top
  • Square Cabochon
  • Square Checkerboard
  • Square Concave Cut
  • Square Facet
  • Square Mixed-Cut
  • Square Rose-Cut
  • Square Step-Cut
  • Square Sugarloaf Cabochon
  • Square with Hole
  • Star Facet
  • Tapered Baguette Cabochon
  • Teardrop Cabochon
  • Trapezoid
  • Trapezoid Cabochon
  • Triangle
  • Triangle Facet
  • Trillion Buff Top
  • Trillion Cabochon
  • Trillion Checkerboard
  • Trillion Concave 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 (139)
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
  • Carnelian
  • Cat's Eye Apatite
  • Cat's Eye Aquamarine
  • Cat's Eye Gemstones
  • Cat's Eye Moonstone
  • Cat's Eye Opal
  • Cat's Eye Scapolite
  • Chalcedony
  • Charoite
  • Chocolate Opal
  • Chrome Diopside
  • Chrysoberyl
  • Chrysocolla
  • Chrysoprase
  • Citrine
  • Color Change Gemstones
  • 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
  • Howlite
  • Hyalite Opal
  • 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
  • Mother of Pearl
  • Mystic Topaz
  • Nuummite
  • Obsidian
  • Onyx
  • 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
  • Rose Quartz
  • Rubellite Tourmaline
  • Ruby
  • Ruby in Fuchsite
  • Ruby-Zoisite
  • Rutile Quartz
  • Sapphire
  • Scapolite
  • 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
  • Strawberry Quartz
  • Sunstone
  • Tanzanite
  • Tiger's Eye
  • Tiger's Eye Matrix
  • Topaz
  • Tourmaline
  • Tsavorite Garnet
  • Turquoise
  • Variscite
  • Zircon
Main Categories
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  • Gemstones By Piece
  • Top Grade Gems
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  • Drilled Gems, Briolettes and Beads
  • Birthstones
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  • Unheated Sapphire
English speaking customer support only

Toll Free - USA & Canada only:
1-800-464-1640

International:
+66-39303404

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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