Gleamite

Yellow rock identification

By The Gleamite desk, Identification research · updated

Yellow finds split on luster before anything else. Glassy translucent yellow points to citrine, opaque saturated yellow to jasper, metallic yellow to pyrite, and crumbly canary yellow to sulfur. Goethite staining fakes the rest. A streak plate retires the metallic candidate, and hardness sorts everything that remains.

Sort by luster before anything else

Yellow is the color where luster does the most work. Four lusters, four branches: glassy translucent yellow belongs to the quartz and fluorite world; dense opaque yellow to jasper; metallic brass to the sulfides; and dull earthy yellow-brown to staining. Each branch then needs exactly one check, which keeps the whole page runnable in two minutes.

StoneLusterThe one checkResult that confirms
CitrineGlassy, translucentSteel nailNo mark; scratches glass
Yellow fluoriteGlassySteel nailNail marks it — Mohs 4
Yellow jasperOpaque, saturatedFlashlight edgeStays dark; nail slides off
Honey calciteGlassy to pearlyVinegarFizzes
PyriteMetallicStreak plateGreenish-black line
Native sulfurBright canary, crumblyFingernail to coinScratches at Mohs 1.5 to 2.5
Goethite stainEarthy coatFile a cornerPale interior, yellow-brown streak

The stained-coat row mirrors the orange problem — goethite and limonite paint quartz and sandstone yellow-brown by the hillside, and the filed-corner test from orange rock identification applies unchanged.

The two yellow traps

The metallic trap is the famous one. Every creek-bed glitter is pyrite until a streak plate says otherwise — the mineral itself is profiled in how to identify pyrite — and the full three-test sequence, shade, dent, streak, lives in how to identify gold in rocks; nothing on a yellow metallic find should be believed before that page’s checks run. The quieter trap is commercial: saturated golden “citrine” clusters with white bases are heated amethyst, a story told in full on the crystal identifier page, and opaque mustard stones sold as yellow jasper get the jasper checks in how to identify jasper.

Shade boundaries stay soft — blush-leaning finds belong in pink rock identification, olive-leaning ones in green rock identification — and whatever the luster tree cannot place goes to the master tables in the rock identification chart.

Questions people ask

What kind of rock is yellow?
By luster: glassy and translucent is citrine or yellow fluorite; opaque and saturated is yellow jasper; metallic is pyrite; earthy yellow-brown is goethite or limonite staining on ordinary rock. Soft, bright canary crystals near hot springs or volcanic ground are native sulfur, the most distinctive of the group.
Is my yellow metallic rock gold?
Almost certainly pyrite, but the test is cheap: drag it across unglazed tile. Pyrite streaks greenish black, gold streaks golden yellow, and no lighting condition changes either answer. Pyrite is also brittle where gold dents, and noticeably lighter in the hand than true gold's extreme heft.
How do I identify citrine in the field?
Look for quartz behavior in yellow: six-sided crystal habit, glassy luster, hardness that scratches glass, and pale-to-honey color that varies across the crystal. Deep orange clusters with white bases are usually heated amethyst sold as citrine. Natural citrine is subtler and much less common than the gift-shop supply suggests.
The Gleamite deskWrites every identification chart on this site from named mineralogical properties — Mohs values, streak colors, specific gravity — sourced from USGS and standard references on a stated date, and runs the same hardness, streak and vinegar checks it tells readers to run.
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