Moissanite vs. Lab-Grown Diamond
A jeweler's honest comparison: how the two stones differ in sparkle, hardness, and price — and which one is right for your ring.
Refractive index — the sparkle question
Moissanite has a refractive index of 2.65–2.69, meaningfully higher than a lab-grown diamond's 2.42. In practice that means more 'fire' — the rainbow flashes you see when a stone moves under light — and more overall brilliance from the same cut. Lab diamonds give a whiter, more classically restrained sparkle. Side-by-side, moissanite reads as livelier; diamond reads as cooler and more uniform. Both are stunning; the difference is character, not quality.
Hardness and everyday durability
Lab-grown diamond is a 10 on the Mohs hardness scale — the hardest natural-or-grown gemstone on earth. Moissanite is a 9.25–9.5, second only to diamond and harder than sapphire, ruby, or any other common engagement-ring center stone. For an heirloom ring worn every day, both will resist scratches, chips and the abrasion of decades of wear. Neither is fragile. Cleaning is identical: warm water, mild dish soap, soft toothbrush.
Price per carat — where the gap is dramatic
This is the most decisive difference. A well-cut 1.5ct moissanite center stone in a 14k recycled-gold setting typically runs $700–$1,400 at Little Luxuries. The same setting with a comparable VS-clarity, F-color 1.5ct lab-grown diamond runs $2,200–$4,000+. The savings compound on larger center stones: at 2.5ct, moissanite stays under $2,000; lab diamond often crosses $6,000. The math lets you buy a larger, better-cut stone, invest in a heavier setting, or simply keep the difference.
How to choose
Choose moissanite if you want maximum visual impact for your budget, love a fiery sparkle, and value being able to upgrade your setting or stone size over time. Choose a lab-grown diamond if you specifically want a diamond's restrained, whiter sparkle, plan to appraise or resell the ring, or place symbolic weight on the word 'diamond.' Both stones are ethically grown, conflict-free, and indistinguishable in toughness for everyday wear.