RocksdayJasper vs Petrified Wood
How to tell them apart
Opaque, impurity-rich microcrystalline quartz. Iron oxides give the classic brick red, but jasper comes in nearly every earthy color and pattern.
Photo: Tommy from Arad, CC BY 2.0
Ancient wood whose cells were replaced, one by one, with quartz — turning a tree into stone.
Photo: Michael Gäbler, CC BY 3.0
Quick tests
- Texture: Petrified Wood is a fossil; Jasper is a single mineral.
Key differences
- Jasper has no wood grain or growth rings.
Side by side
| Property | Jasper | Petrified Wood |
|---|---|---|
| Type | Mineral | Fossil |
| Mohs hardness | 6.5–7 | 6.5–7 |
| Luster | Dull to waxy | Waxy to vitreous |
| Streak | White | — |
| Colors | Red, Brown, Yellow, Green | Brown, Red, Yellow, Gray, Black |
| Crystal system / structure | Microcrystalline quartz (chalcedony) | Wood replaced by silica |
| Specific gravity | 2.5–2.9 | 2.6–2.9 |
| Formula | SiO₂ + impurities | — |
| Found in | Oregon and Idaho; India | Petrified Forest, Arizona; Ginkgo Petrified Forest, Washington |
Properties that are the same for both are grayed out.
How to identify jasper
- Completely opaque, even at thin edges.
- Solid earthy colors, often red, sometimes patterned.
- Hard — scratches glass.
- Smooth, curved fracture surfaces.
Crystal system: Microcrystalline quartz (chalcedony)
Full Jasper guide →How to identify petrified wood
- Visible bark texture, growth rings or wood grain.
- Heavy and hard like agate.
- Colorful bands of red, yellow and brown in polished slices.
Structure: Wood replaced by silica
Full Petrified Wood guide →More comparisons
Could you tell them apart from a blurry close-up?
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