Gold vs Pyrite: Six Tests That Settle It in Two Minutes

Almost every "I found gold" photograph is pyrite. That is not a criticism — pyrite is genuinely gold-coloured, genuinely metallic, and genuinely common, whereas gold is rare enough that most people will never encounter it in the field. The good news is that gold and pyrite differ in nearly every physical property that matters, so you do not need a lab to tell them apart.

Work through these in order. The first two settle most cases.

1. The streak test

Drag the sample firmly across the unglazed back of a ceramic tile.

• Gold leaves a golden yellow line.
• Pyrite leaves greenish black.
• Chalcopyrite leaves greenish black as well.

This is the single most decisive test available to an amateur, it takes five seconds, and it costs nothing. A tile from a hardware store offcut bin works perfectly.

If your sample is too small to streak — a few flakes in a pan, say — skip to the malleability test.

2. The scratch test

Press a steel knife point into the sample and try to cut a groove.

The important detail is what the scratch looks like, not just whether it happened. Gold is malleable: the metal moves aside and piles up at the edges of the groove, like cutting into butter. Pyrite is brittle: it shatters into powder and the "groove" is a trench of crushed grit.

3. The hammer test

Put the sample on a hard surface and tap it — gently — with a hammer.

• Gold flattens. It dents and spreads.
• Pyrite shatters into angular fragments and dark powder.

This destroys the specimen, so use it only on a piece you do not care about, and only after the first two tests were ambiguous.

4. Crystal shape

Look at the shape of the piece.

Pyrite very often grows as cubes with fine parallel striations on the faces, or as twelve-sided pyritohedra. If you can see flat crystal faces with straight edges and parallel grooves, you have pyrite. Gold does not do this at hobbyist scale; natural gold forms irregular blobs, wires, and flattened flakes.

5. Colour under different light

Take the sample outside, then indoors, then hold it at different angles.

Gold stays the same buttery yellow from every angle and in every light. Pyrite is a paler brass yellow that looks distinctly greenish or grey when the light hits it obliquely, and darker where it has begun to tarnish. Chalcopyrite is brassier still and frequently carries an iridescent purple-blue film.

6. Weight

Gold has a specific gravity around 19. Pyrite is about 5. Quartz is 2.65.

That means a gold nugget weighs roughly four times what a same-sized piece of pyrite weighs, and seven times a same-sized pebble. You do not need a scale to notice this — a genuine gold nugget in your palm feels wrong, in the way a lead fishing weight feels wrong compared to a pebble.

In a gold pan this is why gold stays at the bottom while everything else washes away. If your "gold" floats, drifts, or washes over the lip of the pan, it is mica.

The mica case

A separate common mistake: glittering flakes in creek sediment are usually muscovite mica, not gold at all. Mica flakes are weightless, they drift in moving water, and they peel apart into transparent sheets under a fingernail. Gold sinks instantly and cannot be peeled.

The quick check: put the flakes in a jar of water and shake. Mica swirls and settles slowly. Gold drops straight down and stays.

Summary table

If it passes every test

If your sample streaks golden, cuts with a knife, flattens under a hammer, and feels absurdly heavy, then you should take it seriously and get it assayed rather than relying on a web page. A local university geology department, a lapidary club, or a precious metals dealer can confirm it properly.

Be aware that gold recovered from public land is subject to local law — in many jurisdictions panning requires a permit, and in some it is prohibited entirely. Check before you dig.