Comparison · Metamorphic Rocks vs Organic Gem Materials
Anthracite vs Jet
Anthracite and Jet are easy to confuse. Both sit near Mohs 2.5, so a scratch test alone will not separate them. Lean on luster, streak and heft instead. Below is a side-by-side comparison of their properties and the quick tests that separate them.
Key differences between Anthracite and Jet
- Both sit near Mohs 2.5, so a scratch test alone will not separate them. Lean on luster, streak and heft instead.
- Streak color differs: Anthracite leaves a black to dark gray streak on unglazed porcelain, Jet leaves brown.
- Luster is different: Anthracite is submetallic while Jet is waxy.
- They overlap in black, but Anthracite also comes in gray and Jet also comes in brown.
Anthracite vs Jet properties
| Property | Anthracite | Jet |
|---|---|---|
| Type | Metamorphic Rocks | Organic Gem Materials |
| Mohs hardness | 2.5 | 3 |
| Luster | submetallic | waxy |
| Streak | Black to dark gray | Brown |
| Transparency | opaque | opaque |
| Specific gravity | 1.5 | 1.3 |
| Crystal system | varies | amorphous |
| Common colors | Black, Steel gray | Black, Dark brown |
| Rarity | common | uncommon |
| Typical specimen value | $1–$50+ | $5–$300+ |
Which is more valuable?
Jet is usually the more valuable of the two: a typical collector specimen runs about $40 against $8 for Anthracite, and premium Jet can reach $300 or more.
About Anthracite
Anthracite is a hard, shiny, high-carbon coal. It often looks black, compact, lightweight for its size, and glassy to submetallic.
About Jet
Jet is a compact, lightweight black organic gem material formed from fossilized wood. It takes a high polish, feels warm to the touch, and has been used for mourning jewelry and ornaments since antiquity.
Anthracite vs Jet FAQ
Is Anthracite the same as Jet?
No. Anthracite is a metamorphic rock while Jet is a organic gem material. Both sit near Mohs 2.5, so a scratch test alone will not separate them. Lean on luster, streak and heft instead.
How can you tell Anthracite from Jet?
Both sit near Mohs 2.5, so a scratch test alone will not separate them. Lean on luster, streak and heft instead. Streak color differs: Anthracite leaves a black to dark gray streak on unglazed porcelain, Jet leaves brown. Luster is different: Anthracite is submetallic while Jet is waxy.
Which is harder, Anthracite or Jet?
Jet is harder: Mohs 3 against Mohs 2.5 for Anthracite.
Which is more valuable, Anthracite or Jet?
Jet is usually the more valuable of the two: a typical collector specimen runs about $40 against $8 for Anthracite, and premium Jet can reach $300 or more.
