How to identify gold in rocks

The four contenders for every golden glint

Nearly every yellow metallic flash in rock or gravel is one of four minerals. The table is worth reading before the tests, because knowing the opponent tells you which test will be decisive — and the chief opponent has a full portrait of its own in how to identify pyrite.

Mica is the great creek-bed deceiver: it outsparkles gold in sunlight but a single flake lifted on a wet fingertip weighs nothing and bends. Gold flakes are dense enough to sit still at the bottom of a swirled pan while everything else washes over them.

The three tests, in the order that protects the sample

1. Step 1Shade test — costs nothingMove the specimen out of direct light. Gold keeps its warm yellow; pyrite and chalcopyrite go noticeably grayer and duller. Free, instant, non-destructive.
2. Step 2Dent test — marks one spotPress a pin or knife point on one glint. Gold is soft — Mohs 2.5 to 3 — and takes a dent or smear. Pyrite at Mohs 6 resists, then shatters or flakes.
3. Step 3Streak test — removes a traceDrag the specimen, or one picked-out grain, across unglazed tile. Golden-yellow streak means gold. Greenish black means an iron sulfide, whatever the sun said.

Run them in that order. The shade test is free to repeat forever; the dent test leaves a mark; the streak test grinds off material — plate options and reading technique are on the streak test page. On a piece that might be a specimen worth keeping intact, the ordering is the difference between testing and defacing — and if the piece might be more than a curiosity, the elimination sequence in how to identify valuable rocks is the wider frame around this page.

What gold-bearing rock actually looks like

Gold rarely travels alone. In hand samples it favors white to gray quartz veins, especially where the quartz is stained rust-brown or honeycombed by weathered-out sulfides — prospectors read that iron staining as the trail marker. A clean, sugar-white quartz boulder with nothing else in it is scenery; a rusty, vuggy quartz chunk from the same hillside is worth cracking.

The other reliable association is with the very minerals that impersonate it. Pyrite and chalcopyrite grow in the same veins gold does, which is why the streak test matters even in promising rock: a vein can carry real sulfides and no gold at all, and the rock identification chart will place the host rock but never the metal. Only the streak places the metal.

When it is worth an assay

Visible, streak-confirmed gold in rock already beats typical commercial ore grade, where gold runs in invisible grams per ton. At that point stop testing at home: an assay office measures actual content, produces a document a buyer accepts, and costs little against a metal that crossed $3,000 an ounce in March 2025. Panning districts, old mine dumps and regions with documented finds raise the prior — the Upper Peninsula’s Ropes mine country in Michigan rock identification is one mapped example, and the Dahlonega belt in Georgia rock identification has been producing pannable flakes since 1829.

The anti-recommendation is equally firm: skip acid kits entirely. Nitric-acid tests exist for jewelry and add danger without adding certainty on rock samples — the shade, dent and streak sequence answers the same question for a find in the field, and a photo pass with the rock identifier answers the host-rock half for free.