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12 Carat Diamond (Marquise, 23.78×11.89mm, White)

Color:
white
actual size
12ct Diamond displayed at actual size of 23.78×11.89mm, (Marquise cut, White
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Actual size is set for screen


How big is a 12 carat marquise-cut Diamond?

It depends on the cut parameters and length-to-width ratio, but a typical size of a 12ct marquise-cut Diamond would be around 23.78×11.89 mm (±6%). The lw ratio of this Diamond is 2. See below how big it looks on a ring and finger. 
Ring:
Skin tone:
Ring width: 3.0 mm
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Finger image
Ring on finger
White 12ct Diamond (marquise cut) shown in real-world size of 23.78×11.89mm on a ring and finger
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
 71 %
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Ring diameter: 16.9 mm
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Additional Info

Diamond is the hardest natural material (nothing can scratch it, but another diamond) and a very attractive and expensive gem. Diamonds can occur in a whole spectrum of colors, although white or colorless are the most popular.

Where to buy?
For certified gemstones, high-end gemstone jewelry, and birthstone jewelry, see Blue Nile

Gem Details

Name:
Diamond
Shape:
Marquise
Chemical Formula:
C
Crystal Structure:
Isometric
Hardness:
10
Specific Gravity
3.52
Carat weight:
12 ct
Gram weight:
2.4 g (0.0847 ounces)
Points:
1200 pts
Length:
23.78 mm
Width:
11.89 mm
Est. face-up size:
200.75 mm²
Volume:
681.82 mm³
Length-to-width ratio:
2
Refractive Index:
2.417 - 2.419
Luster:
Adamantine
Wearability:
Excellent
Care Instructions:
No special or unusual care
Color:
Diamond can be found in the following colors:
Color WhiteColor Light RedColor RedColor Dark RedColor Orangey RedColor Light OrangeColor OrangeColor Light BrownColor BrownColor Dark BrownColor Light YellowColor YellowColor Light Yellowish GreenColor Yellowish GreenColor Dark Yellowish GreenColor Light Green Color GreenColor Dark GreenColor Light Bluish GreenColor Bluish GreenColor Dark Bluish GreenColor Light BlueColor BlueColor Dark BlueColor Light VioletColor VioletColor Dark VioletColor Light PurpleColor PurpleColor Dark PurpleColor Light GrayColor GrayColor Black
Birthstone:
Diamond is a birthstone for the month of April

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