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1.25 Carat Tanzanite (Round, 6.83mm, Blue)

Color:
blue
actual size
1.25ct Tanzanite displayed at actual size of 6.83×6.83mm, (Round cut, Blue
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How big is a 1.25 carat round-cut Tanzanite?

It depends on the cut proportions, but typically a 1.25ct round-cut Tanzanite would measure around 6.83 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
Blue 1.25ct Tanzanite (round cut) shown in real-world size of 6.83×6.83mm 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
 41 %
Saved...
Ring diameter: 16.9 mm
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Additional Info

Tanzanite is a blue variety of the mineral Zoisite. It got its name after the East African country of Tanzania, were it was discovered in 1967. Most of Tanzanite on the market today is heat treated.

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

Gem Details

Name:
Tanzanite
Mineral Group:
Zoisite
Shape:
Round
Chemical Formula:
Ca2Al3(SiO4)3(OH)
Crystal Structure:
Orthorhombic
Hardness:
6-6.5
Specific Gravity
3.35
Carat weight:
1.25 ct
Gram weight:
0.25 g (0.0088 ounces)
Points:
125 pts
Length:
6.83 mm
Width:
6.83 mm
Average diameter:
6.83 mm
Est. face-up size:
36.64 mm²
Volume:
74.63 mm³
Length-to-width ratio:
1
Refractive Index:
1.69 - 1.70
Luster:
Vitreous
Wearability:
Very good
Care Instructions:
gentle wear recommended
Color:
Tanzanite can be found in the following colors:
Color Light BlueColor BlueColor Dark Blue
Birthstone:
Tanzanite is a birthstone for the month of December

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