Onyx ARAG
Grade
ARAG = aragonite 'onyx marble'
Pick when a denser, slightly harder and more sharply banded translucent stone is wanted for carving and thick blocks.
Values for the ARAG condition
What is Onyx ARAG?
Onyx ARAG is Onyx in the ARAG grade — pick when a denser, slightly harder and more sharply banded translucent stone is wanted for carving and thick blocks. Onyx ARAG has a tensile strength of 6 MPa (0.87 ksi), weaker than 81% of natural material grades. The elastic modulus is 50 GPa (7.25 Msi). Onyx ARAG has a density of 2.82 g/cm³ (0.102 lb/in³), heavier than 98% of natural material grades.
Advantages
- Polishes to a fine finish — 90/100, better than 100% of natural material grades
- Conducts heat well — 2.3 W/m·K (1.33 BTU/hr·ft·°F), better than 91% of natural material grades
- Stiff — 50 GPa (7.25 Msi), better than 88% of natural material grades
- Low embodied carbon — 0.22 kg CO₂/kg, better than 84% of natural material grades
Limitations
- Heavy — 2.82 g/cm³ (0.102 lb/in³), worse than 98% of natural material grades
- Needs corrosion protection — 22/100, worse than 93% of natural material grades
- Difficult to machine — 60/100, worse than 89% of natural material grades
Onyx ARAG properties
Typical room-temperature values for Onyx ARAG; 8 are specific to this condition. Other listed values are Onyx reference data and may not represent this condition. Bars are the position among natural material grades.
Physical2
Onyx ARAG has a density of 2.82 g/cm³ (0.102 lb/in³), heavier than 98% of natural material grades.
Mechanical11
Onyx ARAG has a tensile strength of 6 MPa (0.87 ksi), weaker than 81% of natural material grades. The elastic modulus is 50 GPa (7.25 Msi).
Thermal5
Onyx ARAG is rated for continuous service to 100°C (212 °F). It conducts heat at 2.3 W/m·K (1.33 BTU/hr·ft·°F), better than 91% of natural material grades. Thermal expansion is 8 µm/m·K (4.44 µin/in·°F).
Electrical1
Onyx ARAG has an electrical resistivity of 1,000,000 Ω·m.
Chemical & Environmental1
Corrosion resistance is poor (22/100), worse than 93% of natural material grades.
Sustainability4
Producing a kilogram of Onyx ARAG takes about 3 MJ of energy and emits 0.22 kg of CO₂ — less than 84% of natural material grades. Typical recycled content is 0%.
Manufacturability2
Onyx ARAG's machinability is good (60/100, worse than 89% of natural material grades).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with Onyx ARAG
Is Onyx easy to machine?
Cut wet with continuous-rim diamond blades and light feed; the stone is soft but splits along banding, so support the slab fully and avoid dry cutting or hammer drilling.
Can Onyx be welded?
Not weldable — sections are joined with epoxy/polyester colour-matched adhesive or mechanical anchors, with mitred and glued corners for boxes and vanities.
Can Onyx be formed, bent or molded?
Shaping is subtractive only: CNC routing, waterjet inlay and hand carving all work well because of the low hardness; thin translucent veneers are laminated to glass or honeycomb rather than bent.
What surface finishes work on Onyx?
Takes a very high polish with cerium/tin oxide, but must be impregnated with a solvent-based penetrating sealer and kept away from acids; honed or leathered finishes hide etch marks better in wet areas.
Onyx chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| CaCO3calcite or aragonite; source of translucency and acid sensitivity | 92 – 99.5 | 97 |
| MgCO3 | 0.1 – 3 | 0.8 |
| SiO2detrital quartz/chalcedony | 0.05 – 2.5 | 0.5 |
| Fe2O3iron oxide — honey/amber and red banding | 0.02 – 1.5 | 0.3 |
| Al2O3clay impurity | 0.02 – 1 | 0.2 |
| MnO + Cu/Cr tracesgreen and pink colouration | 0 – 0.3 | 0.05 |
| other (impurities, bound water) | balance | — |
Onyx ARAG — frequently asked
What is Onyx ARAG used for?
Onyx ARAG is typically used for backlit wall panels, decorative countertops, sculptures and vases and feature lighting elements. In short: translucent decorative stone; soft, easily carved; acid-sensitive, needs sealing.
What is the tensile strength of Onyx ARAG?
Onyx ARAG has a typical tensile strength of 6 MPa (0.87 ksi) — weaker than 81% of natural material grades.
Is Onyx ARAG easy to machine?
Reasonably — machinability is rated good (60/100, worse than 89% of natural material grades). Cut wet with continuous-rim diamond blades and light feed; the stone is soft but splits along banding, so support the slab fully and avoid dry cutting or hammer drilling.
Can Onyx ARAG be welded?
Not weldable — sections are joined with epoxy/polyester colour-matched adhesive or mechanical anchors, with mitred and glued corners for boxes and vanities.
What surface finishes work on Onyx ARAG?
Takes a very high polish with cerium/tin oxide, but must be impregnated with a solvent-based penetrating sealer and kept away from acids; honed or leathered finishes hide etch marks better in wet areas.
Can Onyx ARAG be formed, bent or molded?
Shaping is subtractive only: CNC routing, waterjet inlay and hand carving all work well because of the low hardness; thin translucent veneers are laminated to glass or honeycomb rather than bent.
What is the maximum service temperature of Onyx ARAG?
Onyx ARAG is rated for continuous use to about 100°C (212 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Sources
- ASTM C503 — Standard Specification for Marble Dimension Stone — ASTM International (2018)
- ASTM C97/C99/C170/C880 — absorption & density, modulus of rupture, compressive and flexural strength of dimension stone — ASTM International (2018)
- Dimension Stone Design Manual — Natural Stone Institute (formerly MIA+BSI) (2016)
- Handbook of Physical Constants — elastic and thermal properties of carbonate rocks — Geological Society of America (1995)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.