Gems by Brilliance
Gemstone types grouped by brilliance level based on refractive index and optical properties
Brilliance refers to how much light a gemstone reflects back to the eye, determined primarily by its refractive index (RI). Higher RI values create more sparkle and brilliance.
Extremely high refractive index (RI > 2.4) - Diamond-like
| Gem Type | Refractive Index | Investment Ranking |
|---|---|---|
| Diamond | 2.417-2.419 | MODERATELY BULLISH |
| Sphalerite | 2.37-2.43 | MODERATELY BULLISH |
Very high refractive index (RI 1.9-2.4) - Superior light return
| Gem Type | Refractive Index | Investment Ranking |
|---|---|---|
| Blue Zircon | 1.925-2.015 | Not Assessed |
| Demantoid | 1.88-1.94 | BULLISH |
| Hyacinth | 1.925-2.015 | Not Assessed |
| Sphene | 1.885-2.050 | MODERATELY BULLISH |
| White Zircon | 1.925-2.015 | Not Assessed |
| Yellow Zircon | 1.925-2.015 | Not Assessed |
| Zircon | 1.925-2.015 | BEARISH |
High refractive index (RI 1.7-1.9) - Vivid sparkle
| Gem Type | Refractive Index | Investment Ranking |
|---|---|---|
| Alexandrite | 1.746-1.755 | VERY BULLISH |
| Almandine | 1.78-1.81 | VERY BEARISH |
| Andradite | 1.88-1.89 | NEUTRAL |
| Benitoite | 1.757-1.804 | BULLISH |
| Blue Spinel | 1.712-1.736 | BULLISH |
| Garnet | 1.72-1.94 | VERY BEARISH |
| Grossular | 1.73-1.76 | BEARISH |
| Hessonite | 1.74-1.75 | Not Assessed |
| Kyawthuite | 2.16-2.19 | Not Assessed |
| Musgravite | 1.718-1.724 | VERY BULLISH |
| Padparadscha Sapphire | 1.762-1.770 | BULLISH |
| Painite | 1.787-1.816 | VERY BULLISH |
| Pink Sapphire | 1.762-1.770 | Not Assessed |
| Pink Spinel | 1.712-1.736 | MODERATELY BULLISH |
| Pyrope | 1.73-1.76 | BEARISH |
| Red Spinel | 1.712-1.736 | VERY BULLISH |
| Rhodolite | 1.74-1.77 | BEARISH |
| Ruby | 1.762-1.770 | VERY BULLISH |
| Sapphire | 1.762-1.770 | BULLISH |
| Spessartine | 1.79-1.81 | MODERATELY BULLISH |
| Spinel | 1.712-1.736 | MODERATELY BULLISH |
| Taaffeite | 1.719-1.723 | VERY BULLISH |
| Tsavorite | 1.74-1.76 | BULLISH |
| Vietnamese Purple Spinel | 1.712-1.736 | BULLISH |
| Yellow Chrysoberyl | 1.746-1.755 | Not Assessed |
| Yellow Sapphire | 1.762-1.770 | Not Assessed |
Moderate refractive index (RI 1.5-1.7) - Moderate sparkle
Lower refractive index (RI < 1.5) - Soft glow
| Gem Type | Refractive Index | Investment Ranking |
|---|---|---|
| Afghanite | 1.523-1.529 | BULLISH |
| Bastnasite | 1.717-1.818 | BEARISH |
| Blue Fluorite | 1.434 | Not Assessed |
| Calcite | 1.486-1.658 | Not Assessed |
| Fluorite | 1.434 | VERY BEARISH |
| Green Fluorite | 1.434 | Not Assessed |
| Hackmanite | 1.483-1.487 | Not Assessed |
| Purple Fluorite | 1.434 | Not Assessed |
| Rainbow Fluorite | 1.434 | Not Assessed |
| Rhodochrosite | 1.597-1.817 | MODERATELY BULLISH |
| Sodalite | 1.483-1.487 | VERY BEARISH |