1. Rarity & Origin
· Onyx (specifically "calcite onyx" or "onyx marble," not the black silicate gem type) forms in rare cave and spring environments.
· Marble is far more common geologically and quarried in large quantities worldwide (Carrara, Calacatta, etc.).
· Onyx supply is limited, so prices are typically higher per square foot.
2. Appearance
· Onyx is translucent - it glows beautifully when backlit, creating dramatic, high-end visual effects.
· Its banded colors (green, honey, amber, pink, white) are far more exotic than typical marbles.
· Designers prize onyx for statement pieces, not large surfaces.
3. Workability & Fragility
· Onyx is softer and more brittle than marble, which makes it harder to fabricate and transport without damage.
This increases labor and waste costs, which adds to the overall value.
4. Best Use
· Onyx: Accent walls, lighted panels, luxury furniture, vanities.
· Marble: Flooring, countertops, staircases, and large surfaces needing durability.
In Conclusion:
· Onyx is rarer and more luxurious but less practical.
· Marble is more versatile and durable, but less exclusive.
