Calibrated Marquise Cut Gemstones in Size 12x6 mm

Some people by gems by color or price, but for many, it is best to buy gems by shape and size - especially if you're in need of a gem to replace a previous item that was lost or damaged. Calibrated marquise shaped facet cut gems, gemstone carvings and cabochons available in 12 mm x 6 mm sizes. For the largest selection of colored gemstones, Shop GemSelect Online.

As a general guideline, when it comes to calibrated gems, they are not usually expected to be cut to exact measurements and specifications. But rather, they're cut with slight variance in size, though the close approximatation in size is not clearly defined, there are general guidelines for what is considered acceptable. Obviously larger and heavy carat weight stones allow more room in size for variance, while smaller stones may leave little to none. This means a large 30mm calibrated gemstone, could actually be closer to 31 millimeters. For this reason, we recommend to always view the exact size in addition to the calibrated size details. The exact size will inform you of the variance you can expect. Some setting styles are more flexible with variance, such as prong settings, while other styles of mountings may need almost an exact size to the fraction of millimeter.

For calibrated gemstones weighing under one carat, most jewelry settings will accommodate a gem which is within 0.2 mm of the calibrated size in order to fit a standard setting. For gemstones that weigh over one carat, a larger variance is acceptable, often round shape settings will allow 0.3 mm or slightly higher even. This small variance can usually be accommodated for most standard style settings. Round-cut gemstones should also have a greater variance in acceptable size when it comes to calibration; in fact it is usually possible to mount a round stone of any size in the closest standard setting.

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Best place to buy gem stones, dont bother shopping else where. Prices are great, no issues with shipping and customer service is the best.

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Overall Rating -> 10

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I have used this site for sseveral years now. All has been great. I started collection gems from GemSelect for years and wanted to collect at least one of most stones. I loved Safers because the mols is a 9 + and they come in every color. This is the best place to buy gems for the assortment and price. Great place to learn about gems too. Sometimes the shipping is a little on the long side. But I would give them a 9.9 out of 10 !!

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Wonderful selection of gems to choose from. Have made many purchases and was only slightly disappointed once.

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The website is well organized and works fast forward and back. Plenty of filters. Each gem is described in detail and you receive the one pictured. Gem material info and sources available. I would like to see more specifics on sources besides country- at least region or state and in the US with Turquiose which mine. Thanks!

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My only complaint is that there are so many beautiful and affordable stones that I get distracted from what I planned to order.

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Gemstones A-Z

Buy Marquise Shape 12x6 mm Gems

1.74 ct Oval Checkerboard Smoky Quartz, 9.1 x 7.1 mm From Brazil

0.55 ct Loose Purple Sapphire, 6.8 x 4.9 mm Odd Shaped From Madagascar

1.12 carat Orange Sunstone, Oval loose Sunstone from India, Natural Untreated Gem, 8 x 6.1 mm

2.41 carat Oval Rhodolite Garnet, loose Certified Rhodolite Garnet from Tanzania, Natural Untreated Gems, 5 x 4 mm

1.82 ct Pink Morganite, 7.6 mm Round Cut From Afghanistan

2.98 ct Loose Orange Sapphire, 5.2 mm Round Cut From Tanzania

0.82 ct Loose Round Cut Lapis Lazuli, 6 mm From Afghanistan

5.49 ct Loose Oval Cut Mystic Quartz, 13.1 x 11.1 mm From Brazil

0.5 ct Loose Orange Sapphire, 4.9 x 4 mm Octagon Cut From Tanzania

3.83 carat Oval Opal, loose Certified Opal from Australia, Natural Untreated Gem, 14.1 x 10.2 mm

0.75 ct Loose Purple Sapphire, 5.1 x 3.9 mm Oval Cut From Madagascar

9.52 ct White Jadeite, 16.2 x 10.6 mm Oval Cut From Myanmar

1.66 ct Loose Pink Tourmaline, 7.1 mm Round Cabochon From Mozambique

10.15 ct Round Labradorite, 10.2 mm From Madagascar

1.01 ct Blue Kyanite, 7 x 5.1 mm Oval Cut From Nepal

2.25 carat Marquise Cut Pyrope Garnet, loose Certified Pyrope Garnet from Mozambique, Natural Untreated Gems, 10 x 5.2 mm

1.96 ct Round Onyx, 5.5 mm From Sri Lanka

10.76 ct Loose Pear Dendritic Agate, 20.1 x 15.2 mm From India

1.43 carat Orange Hessonite Garnet, Oval loose Hessonite Garnet from Madagascar, Natural Untreated Gem, 7.2 x 5.9 mm

2.45 carat Blue Tanzanite, Oval loose Tanzanite from Tanzania, Natural Gems, 5.9 x 3.8 mm

5.54 carat Yellow Citrine, Pear Shape loose Citrine from Brazil, Natural Untreated Gem, 17.1 x 8.4 mm

0.8 ct Octagon Cut Color-Change Diaspore, 5.4 x 4.8 mm From Turkey

3.51 ct Green Agate, 17.9 x 9.1 mm Carved From India

0.59 ct Purple Spinel, 4.7 mm Round Cut From Tanzania

3.84 ct Round Strawberry Quartz, 9.1 mm From Russia

39.75 ct Oval Bloodstone, 21.7 x 16 mm From Madagascar

2.78 carat Sky Blue Topaz, Trillion loose Topaz from Brazil, Natural Gems, 7.1 x 7.1 mm

1.22 ct Orange Moonstone, 6 mm Round Cut From India

7.4 ct Loose Oval Lapis Lazuli, 11.5 x 9.5 mm From Afghanistan

1.85 ct Loose Orange Moonstone, 7.9 x 7.8 mm Trillion Cut From India

8.68 ct Baguette Labradorite, 10.1 x 8.1 mm From Madagascar

11.09 ct Green Jadeite, 17.2 x 12.4 mm Oval Cut From Myanmar

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