Stromatolite
Stromatolite is fossilized microbial structure, CaCO3 or SiO2 (varies with preservation). In the hand, it rates 3 to 7 (carbonate vs silicified) on the Mohs scale, and it runs grey wavy layers and red and cream domes. Affordable; documented ancient localities carry premiums.
The geology.
Stromatolite carries the formula CaCO3 or SiO2 (varies with preservation). It belongs to the none (layered biogenic rock) system. Its listing category is fossilized microbial structure.
It sits at 3 to 7 (carbonate vs silicified) on the Mohs scale. The surface reads dull to waxy polished. Light behaviour is opaque. Specific gravity runs 2.6 to 2.9. The streak is white to pale. It breaks with uneven fracture.
Stacked wavy layers building little domes and cabbage-head columns, each lamination is a day-shift of ancient microbes trapping sediment, fossilized into stone wallpaper of the early Earth.
It turns up mostly as polished slabs with domed layers, tumbled, spheres or bookends.
The origins.
Ancient carbonate platforms worldwide, Bolivia, Morocco, Australia (Pilbara, 3.4+ billion years), and Minnesota's Mary Ellen jasper; living examples still grow at Shark Bay, Australia.
On value, the database notes: affordable; documented ancient localities carry premiums.
Traditional associations.
In energy work traditions, stromatolite is regarded as the deepest ancestral stone, connecting to life's first patient work.
This is lore, and we label it as lore. The measurable facts are further up the page.
Spotting the real thing.
Stacked wavy layers building little domes and cabbage-head columns, each lamination is a day-shift of ancient microbes trapping sediment, fossilized into stone wallpaper of the early Earth.
Honest material is abundant; ordinary banded jasper is sometimes upsold as 'stromatolite', look for domes and columns, not just stripes.
| Looks like | How to tell them apart |
|---|---|
| Banded agate | Agate bands follow cavity walls evenly; stromatolite laminae dome upward and branch into columns |
| Malachite (banded) | Malachite is vivid green, heavy, and fizzes in acid with green streak |
| Wavy gneiss | Metamorphic banding is crystalline and sparkly, without fine repetitive micro-laminae |
At-home tests.
A loupe and a window seat settle most questions about stromatolite. No workshop required.
| Test | What you should see |
|---|---|
| By eye | Convex-upward domed laminations, often pinching into columns |
| Scratch check | Carbonate types fizz in vinegar; jasperized types scratch glass |
| By eye | Layer thickness varies rhythmically like growth records |
If these checks leave you unsure, that is what appraisers are for. Do not file, heat or soak a piece to find out.
Care & handling.
At 3 to 7 (carbonate vs silicified) on the Mohs scale this is a soft material. Keep it as a display piece, store it apart from harder stones, and skip daily-wear settings.
It breaks with uneven fracture, which is worth knowing before you set it or drop it.
Most damage happens during cleaning, not wearing. Avoid steamers, ultrasonic tanks and anything from under the sink.
A deeper look.
Extended detail on composition, sourcing, authentication and market value.
The physical record
The formula on record is CaCO3 or SiO2 (varies with preservation). Crystal system: None (layered biogenic rock). Specific gravity: 2.6 to 2.9. Streak: White to pale. Cleavage and fracture: Uneven fracture.
How it reaches the market
Ancient carbonate platforms worldwide, Bolivia, Morocco, Australia (Pilbara, 3.4+ billion years), and Minnesota's Mary Ellen jasper; living examples still grow at Shark Bay, Australia.
What it gets confused with
Banded agate: Agate bands follow cavity walls evenly; stromatolite laminae dome upward and branch into columns. Malachite (banded): Malachite is vivid green, heavy, and fizzes in acid with green streak. Wavy gneiss: Metamorphic banding is crystalline and sparkly, without fine repetitive micro-laminae.
What it is worth
Affordable; documented ancient localities carry premiums.
Where buyers get caught
Honest material is abundant; ordinary banded jasper is sometimes upsold as 'stromatolite', look for domes and columns, not just stripes.
One more thing
Stromatolites are Earth's oldest visible fossils, microbial mats like these spent two billion years exhaling the oxygen you're breathing now, making this polished paperweight the ancestor of your atmosphere.
An education-first guide.
There is nothing to buy on this page. Stromatolite is not part of our catalogue, and the guide is here anyway because somebody searching the name deserves a straight answer.
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