40 Carat Topaz (Round, 21.32mm, Blue)
Color:
Actual size is set for screen
How big is a 40 carat round-cut Topaz?
It depends on the cut proportions, but typically a 40ct round-cut Topaz would measure around 21.32 mm (±4%) in diameter. You can check the finger coverage in the simulator below.
Ring:
Skin tone:
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Ring width:
3.0 mm
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Saved...
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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Saved...
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Ring diameter:
16.9 mm
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Additional Info
Topaz is a gemstone of many colors. It’s commonly found colorless (white) and then treated to achieve desired colors. Blue Topaz is the most common and popular color variety.
Where to buy?
For certified gemstones, high-end gemstone jewelry, and birthstone jewelry, see Blue Nile
Gem Details
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Name:
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Topaz |
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Shape:
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Round |
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Chemical Formula:
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Al2SiO4(F,OH)2 |
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Crystal Structure:
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Orthorhombic |
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Hardness:
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8 |
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Specific Gravity
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3.53 |
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Carat weight:
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40 ct |
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Gram weight:
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8 g (0.2822 ounces) |
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Points:
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4000 pts |
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Length:
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21.32 mm |
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Width:
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21.32 mm |
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Average diameter:
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21.32 mm |
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Est. face-up size:
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357 mm² |
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Volume:
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2266.29 mm³ |
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Length-to-width ratio:
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1 |
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Refractive Index:
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1.610 - 1.638 |
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Luster:
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Vitreous |
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Wearability:
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Very good |
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Care Instructions:
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Avoid hard hits or drops |
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Color:
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Topaz can be found in the following colors:
                              
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Birthstone:
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Topaz is a birthstone for the month of December |
Popular comparisons:
- 40ct Topaz (Round, Blue, 21.32 x 21.32) vs. 35ct Ruby (Round, Red, 19.56 x 19.56)
- 40ct Topaz (Round, Blue, 21.32 x 21.32) vs. 38ct Ruby (Round, Red, 20.1 x 20.1)
- 40ct Topaz (Round, Blue, 21.32 x 21.32) vs. 39ct Ruby (Round, Red, 20.27 x 20.27)
- 40ct Topaz (Round, Blue, 21.32 x 21.32) vs. 1ct Diamond (Round, White, 6.5 x 6.5)
- 1ct Topaz (Round, Blue, 6.23 x 6.23) vs. 1ct Diamond (Round, White, 6.5 x 6.5)
- 1ct Topaz (Round, Blue, 6.23 x 6.23) vs. 1ct Tourmaline (Round, Violet, 6.51 x 6.51)
- 8ct Topaz (Round, Blue, 12.47 x 12.47) vs. 1ct Emerald (Emerald, Green, 7.28 x 5.39)
- 2ct Topaz (Round, Blue, 7.85 x 7.85) vs. 1ct Topaz (Round, Blue, 6.23 x 6.23)