Identification guide · Metals & Alloys
How to Identify Bronze
Bronze is usually brown, bronze, and gold with a metallic luster and is opaque. It has a Mohs hardness of 3. A copper coin (Mohs 3.5) scratches it, but a fingernail does not. Its streak is brownish gold to coppery. It is most often confused with Copper, Brass, and Rose Gold; the tests below separate them.
Bronze identification checklist
| Color | Brown, Bronze, Gold, Green patina, Copper brown | Look at a clean, dry surface in daylight. Color zoning, banding or spots are as diagnostic as the hue. |
|---|---|---|
| Luster | Metallic | Turn it under a lamp: a true metallic shine reflects like polished metal and stays opaque at thin edges. |
| Transparency | Opaque | Hold a thin edge up to a bright light and note whether light passes through. |
| Mohs hardness | 3 | A copper coin (Mohs 3.5) scratches it, but a fingernail does not. |
| Streak | Brownish gold to coppery | Drag a corner across unglazed porcelain (the back of a bathroom tile) and check the powder color. |
| Cleavage | None | |
| Fracture | Ductile to uneven | |
| Specific gravity | 8.8 | Very heavy, metallic heft (specific gravity about 8.8). |
Bronze look-alikes and how to tell them apart
Both sit near Mohs 3, so a scratch test alone will not separate them. Lean on luster, streak and heft instead. Bronze vs Copper →
Both sit near Mohs 3, so a scratch test alone will not separate them. Lean on luster, streak and heft instead. Bronze vs Brass →
Both sit near Mohs 3, so a scratch test alone will not separate them. Lean on luster, streak and heft instead. Bronze vs Rose Gold →
Bronze is harder (Mohs 3) than Tin (Mohs 1.5), so Bronze will scratch Tin and not the other way round. A fingernail (Mohs 2.5) scratches it easily.
Field tips
- Look for brown, coppery, or muted golden metal.
- Aged bronze may show green, blue-green, or dark brown patina.
- Bronze is usually warmer and browner than brass.
- Common objects include statues, medals, bells, and antique hardware.
Bronze identification FAQ
How can you tell if a rock is Bronze?
Check the color (brown, bronze, gold, and green patina), the metallic luster, a Mohs hardness of 3 and a brownish gold to coppery streak. Photographing it with the StoneSnap app gives a match in seconds.
What is the hardness of Bronze?
Bronze has a Mohs hardness of 3. A copper coin (Mohs 3.5) scratches it, but a fingernail does not.
What is the difference between Bronze and Copper?
Bronze (Mohs 3, metallic luster) and Copper (Mohs 2.5–3, metallic luster) look alike, but hardness, streak and heft usually separate them. See the full Bronze vs Copper comparison for a side-by-side table.
Is Bronze worth anything?
Entry-level Bronze specimens sell for around $1, typical collector pieces about $25, and premium examples $300 or more depending on size, quality and locality.
What color is Bronze?
Bronze is most often brown, bronze, gold, and green patina. Color varies with impurities and locality, so confirm with hardness and luster rather than color alone.
