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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Gemstones A-Z

Buy Marquise Shape 12x6 mm Gems

5.81 ct Oval Black Opal, 9.1 x 7.1 mm From Ethiopia

4.9 ct Orange Sunstone, 11.9 x 9.8 mm Oval Cut From India

1.7 carat Green Tourmaline, Emerald Cut loose Tourmaline from Mozambique, Natural Untreated Gem, 18.9 x 3.4 mm

3.75 carat Marquise Cut Pyrope Garnet, loose Certified Pyrope Garnet from Mozambique, Natural Untreated Gems, 11.9 x 6 mm

6.45 ct Round Cut Smoky Quartz, 12.8 mm From Brazil

4.15 carat Marquise Cut Pyrope Garnet, loose Certified Pyrope Garnet from Mozambique, Natural Untreated Gems, 12.1 x 6.1 mm

0.46 ct Blue Kyanite, 3.6 mm Round Cut From Nepal

0.87 carat Orange Hessonite Garnet, Cushion loose Hessonite Garnet from Sri Lanka, Natural Untreated Gem, 5.2 x 5.2 mm

53.68 carat Pear Hematite, loose Certified Hematite from Brazil, Natural Untreated Gem, 34.3 x 20.2 mm

2.18 carat White Zircon, Oval loose Zircon from Cambodia, Natural Gems, 6.9 x 5 mm

4.05 carat Pear Shape Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 13.6 x 9.8 mm

8 carat White Zircon, Oval loose Zircon from Cambodia, Natural Gems, 6.1 x 4.1 mm

0.51 carat Purple Sapphire, Pear Shape loose Sapphire from Tanzania, Natural Gem, 7.7 x 3.9 mm

9.25 carat Blue Zircon, Oval loose Zircon from Cambodia, Natural Gem, 12.2 x 8.7 mm

2.93 ct Blue Star Sapphire, 7 x 5.2 mm Oval Cut From Madagascar

1.75 ct Loose Oval Cut Black Opal, 12.4 x 8.3 mm From Ethiopia

1.72 ct Multicolor Mystic Quartz, 8.1 mm Round Concave Cut From Brazil

2.47 carat Square Pyrope Garnet, loose Certified Pyrope Garnet from Mozambique, Natural Untreated Gems, 5 x 4.9 mm

17.33 ct Oval Jasper, 36 x 14.5 mm From Mexico

2.42 carat Yellow Citrine, Oval loose Citrine from Brazil, Natural Untreated Gem, 11.1 x 7.5 mm

7.23 ct Marquise Concave Cut Smoky Quartz, 17.2 x 12 mm From Brazil

8.36 ct Green Amazonite, 7.4 x 7.3 mm Cushion Cut From Madagascar

0.53 carat Green Sapphire, Cushion loose Sapphire from Tanzania, Natural Gem, 4.3 x 4.2 mm

2.15 carat Pear Larimar, loose Certified Larimar from the Dominican Republic, Natural Untreated Gem, 11.9 x 8.1 mm

7.08 ct Oval Strawberry Quartz, 12.2 x 10.1 mm From Brazil

88.08 ct Oval Dendritic Agate, 51 x 33.8 mm From India

0.52 carat Green Sapphire, Cushion loose Sapphire from Tanzania, Natural Gem, 4.3 x 4.2 mm

55.34 ct Oval Jasper, 39 x 23.5 mm From Indonesia

1.06 carat Round Ruby, loose Certified Ruby from Myanmar, Natural Gem, 5.5 mm

4.28 ct Round Cut Strawberry Quartz, 11.1 mm From Russia

1.18 ct Loose Orange Sapphire, 5 mm Round Cut From Tanzania

1.62 carat Green Tourmaline, Emerald Cut loose Tourmaline from Mozambique, Natural Untreated Gem, 13.2 x 3.8 mm

Gemstone Information

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