18 Carat Sapphire (Marquise, 25.48×12.74mm, Blue)
Color:
Actual size is set for screen
How big is an 18 carat marquise-cut Sapphire?
It depends on the cut parameters and length-to-width ratio, but a typical size of an 18ct marquise-cut Sapphire would be around 25.48×12.74 mm (±6%). The lw ratio of this Sapphire is 2. See below how big it looks on a ring and finger.
Ring:
Skin tone:
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Ring width:
3.0 mm
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Saved...
64 mm
| Your settings | |
|---|---|
Ring |
Gold |
Skin tone |
Light |
Ring diameter |
16.9 mm |
Ring width |
3.0 mm |
Finger length |
64 mm |
Finger coverage |
76 % |
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Saved...
|
|
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Ring diameter:
16.9 mm
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Additional Info
Sapphire got its name from the Greek word "sappheiros", which means "blue stone". Today, most people still associate Sapphires with the color blue, however, any gemstone quality Corundum that is not red (Ruby) is actually called Sapphire.
Where to buy?
For certified gemstones, high-end gemstone jewelry, and birthstone jewelry, see Blue Nile
Gem Details
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Name:
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Sapphire |
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Mineral Group:
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Corundum |
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Shape:
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Marquise |
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Chemical Formula:
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Al2O3 |
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Crystal Structure:
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Hexagonal |
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Hardness:
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9 |
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Specific Gravity
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4 |
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Carat weight:
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18 ct |
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Gram weight:
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3.6 g (0.127 ounces) |
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Points:
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1800 pts |
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Length:
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25.48 mm |
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Width:
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12.74 mm |
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Est. face-up size:
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230.48 mm² |
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Volume:
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900 mm³ |
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Length-to-width ratio:
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2 |
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Refractive Index:
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1.76 - 1.77 |
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Luster:
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Vitreous to adamantine |
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Wearability:
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Excellent |
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Care Instructions:
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No special or unusual care |
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Color:
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Sapphire can be found in the following colors:
                           
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Birthstone:
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Sapphire is a birthstone for the month of September |
Popular comparisons:
- 1ct Sapphire (Marquise, Blue, 10 x 5) vs. 1ct Sapphire (Oval, Blue, 10 x 5)
- 1.5ct Sapphire (Marquise, Blue, 11.3 x 5.65) vs. 2ct Diamond (Oval, White, 10.23 x 6.82)
- 1ct Sapphire (Marquise, Dark Green, 10 x 5) vs. 1ct Sapphire (Round, Dark Green, 6 x 6)
- 2ct Sapphire (Marquise, Blue, 12.44 x 6.22) vs. 2ct Diamond (Marquise, White, 13.08 x 6.54)
- 1ct Sapphire (Marquise, Dark Green, 10 x 5) vs. 1ct Sapphire (Pear, Dark Green, 8 x 5)
- 0.1ct Sapphire (Marquise, Blue, 4.58 x 2.29) vs. 0.18ct Emerald (Princess, Green, 3.46 x 3.46)
- 2ct Sapphire (Marquise, Blue, 12.44 x 6.22) vs. 2ct Diamond (Oval, White, 10.23 x 6.82)
- 1.8ct Sapphire (Marquise, White, 12 x 6) vs. 2ct Zircon (Marquise, White, 11.82 x 5.91)