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  : Octagon Shape 12x10 mm Gems
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Gemtype Color Shape Weight Size Date Clarity Price Origin
You Selected (7): Octagon Shape 12x10 mm Gems Clear All
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ID: 3846001 pcs
thumb image of 7.7ct Octagon Facet White Topaz (ID: 384600)
7.71ct Topaz
12.03 x 10.08 x 6.63mm
USD 53.97
Item in Stock
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ID: 3997711 pcs
thumb image of 7.9ct Octagon Facet Bi-Color Ametrine (ID: 399771)
7.85ct Ametrine
11.97 x 10.36 x 7.66mm
USD 37.60
Item in Stock
ID: 4427661 pcs
thumb image of 6.6ct Octagon Facet Bi-Color Ametrine (ID: 442766)
6.63ct Ametrine
12.31 x 9.89 x 7.35mm
USD 33.15
Item in Stock
ID: 4417841 pcs
thumb image of 6ct Octagon Facet Bi-Color Ametrine (ID: 441784)
5.98ct Ametrine
11.56 x 9.68 x 6.22mm
USD 29.90
Item in Stock
ID: 4418401 pcs
thumb image of 5.2ct Octagon Facet Bi-Color Ametrine (ID: 441840)
5.19ct Ametrine
11.68 x 10.12 x 5.24mm
USD 25.95
Item in Stock
ID: 4078411 pcs
thumb image of 5.3ct Octagon Facet Golden Green Apatite (ID: 407841)
5.34ct Apatite
11.58 x 10.40 x 5.30mm
USD 221.88
Item in Stock
ID: 4418341 pcs
thumb image of 6.8ct Octagon Facet Bi-Color Ametrine (ID: 441834)
6.83ct Ametrine
11.77 x 10.26 x 6.92mm
USD 34.15
Item in Stock
Octagon Shape 12x10 mm Gems
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 Octagon shape / Emerald-Cut, faceted and cabochon gems available now in 12 x 10 mm size range. Shop a wide range of calibrated gemstones by size online at wholesale from GemSelect.

As a general guideline, when it comes to 'calibrated' gems, they are not usually expected to be cut to exact measurements. 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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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