Base metals

Bronze

Copper-tin alloy, typically 85–95% copper

Warm golden-brown to amber tones. Deeper and redder than brass; develops a rich patina ranging from brown to green-black over time

Composition

Typically 88–90% copper, 10–12% tin; jewellery bronze may include small amounts of zinc or phosphorus for workability

Physical properties

Density 8.80 g/cm³ Weight per unit volume. Platinum is ~40% heavier than 18k gold at equal size
Melting range 1000–1080 °C Working temperature for alloys. Pure metals have a sharp melting point
Vickers hardness 100 HV Higher HV = greater scratch resistance in service
Mohs hardness 3 Approximate equivalent for comparative reference
Tensile strength 350 MPa Resistance to breaking under tension, relevant for prongs and fine settings
Tarnish resistance Moderate Surface oxidation / sulphidation under typical wear conditions
Workability Good Ease of forming, soldering, and fabricating under standard jewellery workshop conditions
Hypoallergenic Allergy risk Likelihood of triggering skin reactions under normal wear

Common uses

Craft and art jewellery, sculptural pieces, ancient and reproduction jewellery, mixed-metal work, tribal and ethnic jewellery styles, belt buckles and clasps

Hallmarking & identification

No precious metal hallmark. Not considered a fine metal. Historical importance: most ancient jewellery from the Bronze Age through the medieval period was bronze. Still widely used by independent jewellers and craft artists for its warm colour and workability.

Care & maintenance

Patinas naturally over time; the colour shift is intentional in many designs. Clean with warm soapy water to slow patina. Remove existing patina with a commercial metal polish or a paste of lemon juice and salt if a bright finish is preferred. Can leave green marks on skin from copper-skin acid reaction; harmless but noticeable.

Market & pricing

Very low material cost. Fabricated pieces are priced primarily on craftsmanship. Extremely accessible for studio jewellers and beginners.