18 Carat Diopside (Emerald, 17.85×13.22mm, Green)

Color:

green

actual size

Actual size is set for screen

How big is an 18 carat emerald-cut Diopside?

It depends on the cut parameters and length-to-width ratio, but a typical size of an 18ct emerald-cut Diopside would be around 17.85×13.22 mm (±6%). The lw ratio of this Diopside is 1.35. See below how big it looks on a ring and finger.

Ring:

Gold
Platinum

Skin tone:

Pale
Light
Medium
Dark

Ring width: 3.0 mm

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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	79 %

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Ring diameter: 16.9 mm

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Additional Info

Diopside is a beautiful and affordable gem with rich green color that rivals the beauty of Emerald and Tsavorite. Its name comes from Greek words dis (meaning "double") and opsis (meaning "appearance"), referring to its crystal shape.

Where to buy?

For certified gemstones, high-end gemstone jewelry, and birthstone jewelry, see Blue Nile

Gem Details

Name:	Diopside
Shape:	Emerald
Chemical Formula:	(Ca,Cr)MgSi₂O₆
Crystal Structure:	Monoclinic
Hardness:	5-6
Specific Gravity	3.3
Carat weight:	18 ct
Gram weight:	3.6 g (0.127 ounces)
Points:	1800 pts
Length:	17.85 mm
Width:	13.22 mm
Est. face-up size:	219.46 mm²
Volume:	1090.91 mm³
Length-to-width ratio:	1.35
Refractive Index:	1.668 - 1.703
Luster:	Vitreous
Wearability:	Moderate
Care Instructions:	Relatively soft and prone to scratching
Color:	Diopside can be found in the following colors:
Birthstone:	Diopside is a birthstone for the month of March

Popular comparisons:

About Diopside Specific Gravity

Diopside has a specific gravity of approximately 3.22 - 3.38, with 3.3 being a generally accepted standard average for gem-quality material.

For all the Diopside size calculations on this website, the specific gravity of 3.3 is used.

To learn more about it and why it matters, and to compare densities of all the gemstones on one page, click here.

Ring & Finger Simulator

Use the simulator on this page to play around with different ring and finger configurations.

To select a different gemstone, shape, color or size, or to compare two gems side-by-side, use the form at the top of the page. Comparison example: 18ct Diopside vs Tsavorite (Emerald Cut)

If you want to compare emerald-cut Diopside sizes from 0.25 to 40ct on one page, see Emerald Cut Diopside Size Chart

In order to view real-world sizes on your screen, ensure that the actual size is set to your device screen size (diagonal in inches).