Moissanite, diamond, and zircon are all popular gemstones used in jewelry. Here are some differences between them:

Composition: Moissanite is made of silicon carbide, whereas diamonds are made of carbon. Zircon, on the other hand, is a natural mineral that is composed of zirconium silicate.

Hardness:

Diamonds are the hardest natural substance on earth with a rating of 10 on the Mohs scale of hardness. Moissanite is also a very hard gemstone, with a rating of 9.25 on the Mohs scale. Zircon is not as hard as moissanite or diamond and has a rating of 7.5 on the Mohs scale.

Brilliance and Fire:

Moissanite is known for its exceptional brilliance and fire, which is why it is often used as a diamond alternative in engagement rings and other fine jewelry. Diamonds are also known for their brilliance and fire, but they have a different type of sparkle than moissanite. Zircon has good brilliance and a high refractive index, but it is not as sparkly as moissanite or diamond.

Color:

Diamonds can range in color from colorless to yellow or brown, but the most valuable diamonds are colorless. Moissanite is typically colorless or near colorless. Zircon can come in a range of colors, including white, blue, red, and green.

Cost:

Moissanite is generally less expensive than diamonds, but it is more expensive than zircon. Diamonds are the most expensive of the three gemstones. Ultimately, the choice between moissanite, diamond, and zircon will depend on personal preferences and budget. Each gemstone has its own unique characteristics and beauty, so it's important to choose the one that speaks to you.

Property	Diamond	Moissanite	Zircon
Chemical Formula	C	SiC	ZrSiO4
Hardness	10	9.25	7.5-8.0
Refractive Index	2.42	2.65	1.93-1.98
Dispersion	0.044	0.104	0.039
Color	Can be colorless or	Can be colorless or	Can come in a range
	come in a range of	come in a range of	of colors including
	colors including	colors including green,	blue, red, orange,
	yellow, pink, blue,	yellow, and gray-green	brown, and yellow
	and red
Brilliance	Excellent	Excellent	Good
Price	Expensive	Less expensive than diamond	Least expensive of the three

Note: Moissanite is a laboratory-grown gemstone and has some optical properties that make it appear similar to diamonds. Zircons, on the other hand, are natural gemstones that can be found in a variety of colors but are not typically as hard or brilliant as diamonds or moissanite. The information in the table is a general guide and may vary depending on the specific characteristics of each gemstone.