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Gemstone Property References

Specific gravity is the ratio of a material’s density to the density of water and has no unit. These typical reference values describe gem materials, not measurements of individual RU EM SA stones.

GemstoneSpecific gravity
Ruby3.97 to 4.05
Emerald2.67 to 2.78
Yellow Sapphire3.95 to 4.03
Diamond3.50 to 3.53
Pearl2.60 to 2.85
Red Coral2.60 to 2.70
Blue Sapphire3.95 to 4.03
Hessonite Garnet3.62 to 3.67
Cat’s Eye3.70 to 3.78
Amethyst2.65
Citrine2.65
Rose Quartz2.65
Moonstone2.56 to 2.59
Turquoise2.31 to 2.84
Opal1.98 to 2.20
Aquamarine2.68 to 2.74
Morganite2.71 to 2.90
Peridot3.22 to 3.45
Sunstone2.62 to 2.65
Labradorite2.65 to 2.75
Agate2.60 to 2.64
Carnelian2.58 to 2.64
Tourmaline2.82 to 3.90
Lapis Lazuli2.50 to 3.00
Topaz3.49 to 3.57
Zircon3.93 to 4.73
Tiger’s Eye2.58 to 2.64

Sources

Reviewed 27 October 2026. Composition, inclusions and other natural differences can affect specific gravity.