Niobium
Pure niobium or high-purity alloy
Natural silver-grey in pure form. Anodising produces vivid, stable colours (blue, gold, purple, green, pink) through thin-film light interference without dyes or coatings
Composition
Pure niobium; occasionally alloyed with zirconium for medical implants
Physical properties
| Density | 8.57 g/cm³ | Weight per unit volume. Platinum is ~40% heavier than 18k gold at equal size |
|---|---|---|
| Melting range | 2477 °C | Working temperature for alloys. Pure metals have a sharp melting point |
| Vickers hardness | 110 HV | Higher HV = greater scratch resistance in service |
| Mohs hardness | 6 | Approximate equivalent for comparative reference |
| Tensile strength | 275 MPa | Resistance to breaking under tension, relevant for prongs and fine settings |
| Purity | 99.90% | Fine metal content by mass |
| Tarnish resistance | Excellent | Surface oxidation / sulphidation under typical wear conditions |
| Workability | Good | Ease of forming, soldering, and fabricating under standard jewellery workshop conditions |
| Hypoallergenic | Hypoallergenic | Likelihood of triggering skin reactions under normal wear |
Common uses
Body piercing jewellery (high biocompatibility), hypoallergenic earring hooks and findings, anodised coloured jewellery, contemporary art jewellery, medical implant components
Hallmarking & identification
No precious metal hallmark. May be stamped Nb or Niobium. Considered one of the most biocompatible metals for body jewellery alongside titanium and implant-grade steel. Approved for initial piercings in many professional piercing standards.
Virtually maintenance-free. Clean with warm soapy water. Anodised colours are structural (thin-film interference) and do not chip or peel, but deep scratches may affect the visual effect. Cannot be re-anodised at home without specialist equipment.
Market & pricing
More expensive than titanium and stainless steel but significantly cheaper than precious metals. Niche availability through specialist jewellery suppliers and piercing suppliers.