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4 Carat Kyanite (Marquise, 15.86×7.93mm, Blue)

Color:
blue
actual size
4ct Kyanite displayed at actual size of 15.86×7.93mm, (Marquise cut, Blue
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Actual size is set for screen


How big is a 4 carat marquise-cut Kyanite?

It depends on the cut parameters and length-to-width ratio, but a typical size of a 4ct marquise-cut Kyanite would be around 15.86×7.93 mm (±6%). The lw ratio of this Kyanite is 2. See below how big it looks on a ring and finger. 
Ring:
Skin tone:
Ring width: 3.0 mm
Saved...
Finger image
Ring on finger
Blue 4ct Kyanite (marquise cut) shown in real-world size of 15.86×7.93mm 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
 47 %
Saved...
Ring diameter: 16.9 mm
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Additional Info

Kyanite got its name from the Greek word "kyanos", which simply means "blue". Gems with intense sapphire blue color are the most valuable. One peculiarity about Kyanite is that depending on crystallographic direction, it has two different hardnesses (7 and 4.5).

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

Gem Details

Name:
Kyanite
Shape:
Marquise
Chemical Formula:
Al2SiO5
Crystal Structure:
Triclinic
Hardness:
4.5-7
Specific Gravity
3.68
Carat weight:
4 ct
Gram weight:
0.8 g (0.0282 ounces)
Points:
400 pts
Length:
15.86 mm
Width:
7.93 mm
Est. face-up size:
89.3 mm²
Volume:
217.39 mm³
Length-to-width ratio:
2
Refractive Index:
1.710 - 1.735
Luster:
Vitreous,Pearly
Wearability:
Very good
Care Instructions:
Should be treated gently
Color:
Kyanite can be found in the following colors:
Color Light Bluish GreenColor Bluish GreenColor Dark Bluish GreenColor Light BlueColor BlueColor Dark Blue
Birthstone:
Kyanite is not an official birthstone of any month

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