Precious Metal 24K-H01
Supply condition
GB Au999 · ISO 9202
H01 = quarter hard
Pick when soft gold is too limp to handle but deep forming is still required.
Values for the H01 condition
Other 24K tempers and conditions
24K is listed in 5 conditions; see the grade overview at 24K.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
As fabricated | Choose the as-cast state for poured investment bars, coin and ingot stock and traditional cast fine-gold jewellery before any working; strength is only 105 MPa tensile at 22 HB. | 25 | 105 | 30 | 22 HB | 71 % IACS |
ODefault Annealed | Default stocked condition for jewellery sheet/wire, coin blanks and forming stock; maximum ductility, minimum hardness. | 30 | 125 | 45 | 25 HB | 71 % IACS |
H01This page Quarter hard | Pick when soft gold is too limp to handle but deep forming is still required. | 70 | 145 | 30 | 34 HB | 70 % IACS |
Half hard | Compromise temper for bezels, findings and stampings needing some spring-back and dent resistance. | 120 | 170 | 15 | 43 HB | 69 % IACS |
Full hard | Maximum strength/hardness obtainable in pure gold — used for fine wire, contact springs and thin foil where handling strength matters. | 200 | 220 | 4 | 55 HB | 68 % IACS |
What is 24K-H01?
24K-H01 is 24K supplied in the H01 condition — pick when soft gold is too limp to handle but deep forming is still required. 24K-H01 has a yield strength of 70 MPa (10.2 ksi) and a tensile strength of 145 MPa (21 ksi) — weaker than 90% of precious metal grades. Elongation at break is 30% and the elastic modulus is 78 GPa (11.3 Msi). 24K-H01 has a density of 19.32 g/cm³ (0.698 lb/in³), heavier than 91% of precious metal grades. It melts at 1,064°C (1,947 °F). O is the default condition FabDigit quotes; H01 is available on request or by drawing note.
Advantages
- Readily welded — 90/100, better than 99% of precious metal grades
- Good corrosion resistance — 100/100, better than 98% of precious metal grades
- Conducts heat well — 315 W/m·K (182 BTU/hr·ft·°F), better than 76% of precious metal grades
- High electrical conductivity — 70 % IACS, better than 75% of precious metal grades
Limitations
- Limited service temperature — 100°C (212 °F), worse than 100% of precious metal grades
- High embodied carbon — 20,000 kg CO₂/kg, worse than 97% of precious metal grades
- Heavy — 19.32 g/cm³ (0.698 lb/in³), worse than 91% of precious metal grades
- Low strength — 70 MPa (10.2 ksi), worse than 90% of precious metal grades
- Low stiffness — 78 GPa (11.3 Msi), worse than 90% of precious metal grades
24K-H01 properties
Typical room-temperature values for 24K-H01; 18 are specific to this condition. Other listed values are 24K reference data and may not represent this condition. Bars are the position among precious metal grades.
Physical3
24K-H01 has a density of 19.32 g/cm³ (0.698 lb/in³), heavier than 91% of precious metal grades. It melts at 1,064°C (1,947 °F).
Mechanical12
24K-H01 has a yield strength of 70 MPa (10.2 ksi) and a tensile strength of 145 MPa (21 ksi) — weaker than 90% of precious metal grades. Elongation at break is 30% and the elastic modulus is 78 GPa (11.3 Msi).
Thermal6
24K-H01 is rated for continuous service to 100°C (212 °F). It conducts heat at 315 W/m·K (182 BTU/hr·ft·°F), better than 76% of precious metal grades. Thermal expansion is 14.2 µm/m·K (7.89 µin/in·°F).
Electrical3
24K-H01 conducts electricity at 70 % IACS, better than 75% of precious metal grades.
Chemical & Environmental3
Corrosion resistance is excellent (100/100), better than 98% of precious metal grades.
Sustainability4
Producing a kilogram of 24K-H01 takes about 250,000 MJ of energy and emits 20,000 kg of CO₂ — more than 95% of precious metal grades. Typical recycled content is 28%.
Manufacturability8
24K-H01's machinability is poor (34/100, worse than 79% of precious metal grades); weldability excellent (90/100); formability excellent (85/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 24K-H01
Is 24K easy to machine?
Extremely gummy — use razor-sharp polished carbide or diamond tooling, high speed, light depth of cut and minimal or oil-based lubricant; collect all swarf for refining.
Can 24K be welded?
Laser or micro-TIG welds cleanly with no flux and no oxide problem; filler is normally the same 999 gold, and torch soldering with gold solders is routine.
Can 24K be formed, bent or molded?
The most malleable metal available: unlimited cold rolling, deep drawing, beating to sub-micron leaf and coining, with anneals at 500–700 °C whenever work hardening becomes inconvenient.
What surface finishes work on 24K?
Finished by burnishing, tumbling and rouge polishing to a mirror; no plating or anodising is needed or possible, but the surface scratches and dents very easily in service.
24K 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 |
|---|---|---|
| Agprincipal residual | ≤ 0.05 | 0.02 |
| Curesidual | ≤ 0.05 | 0.02 |
| Feresidual | ≤ 0.01 | 0 |
| Pbresidual; limited for hot-working ductility | ≤ 0.01 | 0 |
| Other impurities totalper GB/T 4134 / ISO 9202 | ≤ 0.1 | 0.05 |
| AuAu999 = 999 ‰ minimum fineness; investment grades are Au9999 (99.99 %) or Au99999 | ≥ 99.9 (balance) | — |
24K-H01 — frequently asked
What is 24K-H01 used for?
24K-H01 is typically used for gold bullion bars, coins, traditional Chinese jewelry and electrical contact plating. In short: most malleable metal available; highest-purity gold grade; no structural strength.
What is the yield strength of 24K-H01?
24K-H01 has a typical yield strength of 70 MPa (10.2 ksi) and a tensile strength of 145 MPa (21 ksi) — weaker than 90% of precious metal grades. Strength varies by condition: see the 5 listed tempers.
Is 24K-H01 easy to machine?
Not especially — machinability is rated poor (34/100, worse than 79% of precious metal grades). Extremely gummy — use razor-sharp polished carbide or diamond tooling, high speed, light depth of cut and minimal or oil-based lubricant; collect all swarf for refining.
Can 24K-H01 be welded?
Yes — weldability is rated excellent (90/100). Laser or micro-TIG welds cleanly with no flux and no oxide problem; filler is normally the same 999 gold, and torch soldering with gold solders is routine.
What surface finishes work on 24K-H01?
Finished by burnishing, tumbling and rouge polishing to a mirror; no plating or anodising is needed or possible, but the surface scratches and dents very easily in service.
Can 24K-H01 be formed, bent or molded?
The most malleable metal available: unlimited cold rolling, deep drawing, beating to sub-micron leaf and coining, with anneals at 500–700 °C whenever work hardening becomes inconvenient.
What is the maximum service temperature of 24K-H01?
24K-H01 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.
What is the difference between 24K-O and 24K-H04?
O is the default condition — default stocked condition for jewellery sheet/wire, coin blanks and forming stock; maximum ductility, minimum hardness. H04: maximum strength/hardness obtainable in pure gold — used for fine wire, contact springs and thin foil where handling strength matters. Yield strength is 30 MPa in O versus 200 MPa in H04.
Sources
- ISO 9202 Jewellery — Fineness of precious metal alloys — ISO (2019)
- GB/T 4134 (Gold ingots) — SAC (2015)
- ASM Handbook Vol. 2 — Properties of Precious Metals — ASM International (1990)
- CRC Handbook of Chemistry and Physics — Properties of the Elements — CRC Press (2022)
- World Gold Council technical & sustainability data (gold properties, emissions intensity) — WGC (2023)
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.