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30 Carat Amethyst (Round, 21.31mm, Violet)

Color:
violet
actual size
30ct Amethyst displayed at actual size of 21.31×21.31mm, (Round cut, Violet
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How big is a 30 carat round-cut Amethyst?

It depends on the cut proportions, but typically a 30ct round-cut Amethyst would measure around 21.31 mm (±4%) in diameter. You can check the finger coverage in the simulator below. 
Ring:
Skin tone:
Ring width: 3.0 mm
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Finger image
Ring on finger
Violet 30ct Amethyst (round cut) shown in real-world size of 21.31×21.31mm 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
 127 %
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Ring diameter: 16.9 mm
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Additional Info

Amethyst is a purple variety of quartz and a very popular and affordable gem. Its name originates from the Greek word amethystos which means "not drunken". Ancient Greeks believed it could prevent intoxication. Amethyst is considered the most valuable of quartz gemstones.

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

Gem Details

Name:
Amethyst
Mineral Group:
Quartz
Shape:
Round
Chemical Formula:
SiO2
Crystal Structure:
Hexagonal
Hardness:
7
Specific Gravity
2.65
Carat weight:
30 ct
Gram weight:
6 g (0.2116 ounces)
Points:
3000 pts
Length:
21.31 mm
Width:
21.31 mm
Average diameter:
21.31 mm
Est. face-up size:
356.66 mm²
Volume:
2264.15 mm³
Length-to-width ratio:
1
Refractive Index:
1.54 - 1.55
Luster:
Vitreous
Wearability:
Very good
Care Instructions:
No special or unusual care
Color:
Amethyst can be found in the following colors:
Color Light VioletColor VioletColor Dark VioletColor Light PurpleColor PurpleColor Dark Purple
Birthstone:
Amethyst is a birthstone for the month of February

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