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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over the experience was similar to other sites i have used. The only real note I have is the checkout experience was tedious and discriminatory, i wouldn't accept visa gift cards, which not only have guaranteed funds but help protect from misuse of personal information, but would not accept my visa b/c it is a prepaid card. I don't have bank account and I have been using the prepaid card for years without issue so this was disappointing to me. I feel safer using reputable gem sites rather than amazon or ebay (I have been sold fake gems with fake certs on both), but not being able to use my own valid legitimate funds and having to find a friend to buy for me b/c I use a non-bank card like 40% of the country is insulting.

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Gemstones A-Z

Buy Marquise Shape 12x6 mm Gems

1.22 carat Pear Shape Pyrope Garnet, loose Certified Pyrope Garnet from Mozambique, Natural Untreated Gems, 7 x 4.7 mm

2.44 carat Yellow Citrine, Cushion loose Citrine from Brazil, Natural Untreated Gem, 10.7 x 7.6 mm

41.77 ct Oval Charoite, 31.1 x 23.5 mm From Russia

14.18 ct Black Spinel, 12 mm Round Rose Cut From Thailand

3.44 carat Swiss Blue Topaz, Pear Shape loose Topaz from Brazil, Natural Gems, 6.1 x 4.2 mm

6.94 ct White Moonstone, 9.2 mm Round Cut From India

2.07 carat Square Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gems, 6 x 6 mm

7.83 carat Sky Blue Topaz, Marquise Cut loose Topaz from Brazil, Natural Gems, 13.8 x 8.1 mm

3.45 carat Brown Tourmaline, Pear Shape loose Tourmaline from Mozambique, Natural Untreated Gems, 8.1 x 5.4 mm

2.76 ct Orange Sunstone, 6 x 4.2 mm Oval Cut From Russia

3.71 carat Green Tourmaline, Carved Fruit loose Tourmaline from Mozambique, Natural Untreated Gem, 12.1 x 8.5 mm

3.2 ct Loose Baguette Labradorite, 8.9 x 7.2 mm From Madagascar

0.52 carat Blue Tanzanite, Pear Shape loose Tanzanite from Tanzania, Natural Gems, 5 x 3.8 mm

0.64 carat London Blue Topaz, Oval loose Topaz from Brazil, Natural Gem, 6.2 x 4.3 mm

10.22 carat Pear Charoite, loose Certified Charoite from Russia, Natural Untreated Gem, 21.7 x 12.6 mm

3.28 carat Green Tourmaline, Emerald Cut loose Tourmaline from Mozambique, Natural Untreated Gem, 22.8 x 4.2 mm

11.62 carat Uvarovite Garnet Drusy, loose Certified Uvarovite Garnet Drusy from Russia, Natural Untreated Gem, 19.1 x 11.3 mm

1.6 ct Yellow Beryl, 8.9 x 6.9 mm Cushion Cut From Madagascar

1.13 carat Orange Zircon, Diamond-Cut loose Zircon from Cambodia, Natural Untreated Gem, 5.9 mm

0.73 ct Yellow Beryl, 7.2 x 5.2 mm Oval Cut From Madagascar

14.76 carat Pear Dendritic Agate, loose Certified Dendritic Agate from India, Natural Untreated Gem, 20.7 x 15.1 mm

3.02 carat Blue Tanzanite, Oval loose Tanzanite from Tanzania, Natural Gem, 10 x 7.9 mm

1.73 ct Oval Sillimanite Cat's Eye, 7.7 x 5.7 mm From Madagascar

10.38 ct Loose Fancy Moss Agate, 25.6 x 14.6 mm From India

7.38 ct Octagon Cut Smoky Quartz, 11.8 x 11.7 mm From Brazil

19.09 ct Oval Agate, 18.1 x 15.6 mm From Indonesia

0.76 ct Loose Purple Sapphire, 4.9 x 4 mm Oval Cut From Madagascar

29.36 ct Carved Rose Quartz, 31.2 x 18 mm From South Africa

7.28 ct Pink Moonstone, 15.3 x 15.2 mm Carved From India

3.24 carat Carved Leaf Pyrope Garnet, loose Certified Pyrope Garnet from Mozambique, Natural Untreated Gem, 13.1 x 10.5 mm

7.36 ct Fancy Fire Agate, 16.9 x 9.7 mm From Mexico

0.53 ct Loose Violet Sapphire, 5.9 x 4 mm Oval Cut From Tanzania

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