Metals & Alloys · common
Brass
Brass is a yellow-gold copper and zinc alloy often used in hardware, decorative objects, instruments, keys, fittings, and jewelry findings.
Also known as: Yellow brass, Brass alloy, Copper-zinc alloy.
Brass properties at a glance
| Type | Metals & Alloys |
|---|---|
| Chemical formula | Copper-zinc alloy; composition varies |
| Mohs hardness | 3.5 |
| Luster | metallic |
| Streak | Yellow-gold to brass |
| Cleavage | None |
| Fracture | Ductile to uneven |
| Specific gravity | 8.5 |
| Transparency | opaque |
| Common colors | Yellow gold, Brass yellow, Brown, Tarnished gold |
| Rarity | common |
Geology & background
Brass is manufactured by alloying copper with zinc, then casting, rolling, machining, or stamping it into objects.
Brass has been used for centuries in decoration, instruments, fittings, coins, and mechanical parts because it is workable and corrosion resistant.
How to identify Brass
- Look for a warm yellow-gold metal color.
- Brass is usually yellower than bronze and less orange-red than copper.
- Tarnished areas may appear brown, olive, or dull gold.
- Common objects include keys, fittings, screws, handles, and instruments.
Full Brass identification guide: checklist, home tests and look-alikes →
Brass vs similar stones
Not sure it isn't something else? Side-by-side comparisons with the stones most often confused with Brass.
Where Brass is found
Brass is manufactured, refined, recycled, or traded worldwide; verify grade, purity, and origin from markings, documentation, or provenance when available.
How much is Brass worth?
| Entry-level specimen | $1 |
|---|---|
| Typical collector specimen | $15 |
| Premium specimen | $150+ |
Value depends mostly on the object, purity or alloy grade, weight, brand, condition, markings, and whether it is jewelry, hardware, a coin, a tool, or a raw material sample.
Common uses
- Keys and locks
- Decorative hardware
- Musical instruments
- Fittings and fasteners
- Jewelry findings
Interesting facts
- Brass often looks more yellow than bronze.
- Tarnished brass can darken to brown or muted olive tones.
- Keys, screws, fittings, and many decorative objects are commonly brass.
Care & safety
Brass can scratch, dent, tarnish, corrode, or lose its surface finish depending on the alloy, coating, and use wear.
Check sharp edges. Manufactured metal objects can have sharp edges, burrs, broken points, or worn plating; handle damaged pieces carefully.
Brass FAQ
What is Brass?
Brass is a yellow-gold copper and zinc alloy often used in hardware, decorative objects, instruments, keys, fittings, and jewelry findings.
How much is Brass worth?
Entry-level Brass specimens sell for around $1, a typical collector specimen for about $15, and premium pieces for $150 or more. Value depends mostly on the object, purity or alloy grade, weight, brand, condition, markings, and whether it is jewelry, hardware, a coin, a tool, or a raw material sample.
How hard is Brass?
Brass has a Mohs hardness of 3.5. A steel knife blade (Mohs 5.5) scratches it; a copper coin does not.
What is Brass used for?
Brass is used for keys and locks, decorative hardware, musical instruments, fittings and fasteners, and jewelry findings.
