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13 Carat Tanzanite (Oval, 19.13×12.75mm, Blue)

Color:
blue
actual size
13ct Tanzanite displayed at actual size of 19.13×12.75mm, (Oval cut, Blue
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Actual size is set for screen


How big is a 13 carat oval-cut Tanzanite?

It depends on the cut parameters and length-to-width ratio, but a typical size of a 13ct oval-cut Tanzanite would be around 19.13×12.75 mm (±6%). The lw ratio of this Tanzanite is 1.5. 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 13ct Tanzanite (oval cut) shown in real-world size of 19.13×12.75mm 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
 76 %
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:
Oval
Chemical Formula:
Ca2Al3(SiO4)3(OH)
Crystal Structure:
Orthorhombic
Hardness:
6-6.5
Specific Gravity
3.35
Carat weight:
13 ct
Gram weight:
2.6 g (0.0917 ounces)
Points:
1300 pts
Length:
19.13 mm
Width:
12.75 mm
Est. face-up size:
200 mm²
Volume:
776.12 mm³
Length-to-width ratio:
1.5
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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