Comparison · Quartz Family
Quartz vs Smoky Quartz
Quartz and Smoky Quartz are easy to confuse because both are quartz family. Both sit near Mohs 7, 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 Quartz and Smoky Quartz
- Both sit near Mohs 7, so a scratch test alone will not separate them. Lean on luster, streak and heft instead.
- Hold a thin edge to the light: Quartz is Transparent to translucent, Smoky Quartz is transparent.
- They overlap in black, gray, and brown, but Quartz also comes in clear, purple, yellow, and pink.
- Well-formed crystals give it away: Quartz is Trigonal, Smoky Quartz is hexagonal.
Quartz vs Smoky Quartz properties
| Property | Quartz | Smoky Quartz |
|---|---|---|
| Type | Quartz Family | Quartz Family |
| Mohs hardness | 7 | 7 |
| Luster | Vitreous, greasy on fracture surfaces | vitreous |
| Streak | White | White |
| Transparency | Transparent to translucent | transparent |
| Specific gravity | 2.65 | 2.65 |
| Crystal system | Trigonal | hexagonal |
| Common colors | Colorless, White, Purple (amethyst), Yellow (citrine), Pink (rose), Brown/black (smoky) | Brown, Gray, Black |
| Rarity | common | common |
| Typical specimen value | $5–$250+ | $5–$150+ |
Which is more valuable?
Quartz is usually the more valuable of the two: a typical collector specimen runs about $35 against $30 for Smoky Quartz, and premium Quartz can reach $250 or more.
About Quartz
Quartz is silicon dioxide, SiO2, one of the most abundant minerals in Earth's continental crust, crystallizing in the trigonal division of the hexagonal crystal system with a hardness of 7 that makes it a standard reference point on the Mohs scale. Its six-sided prismatic crystals, often terminated by pyramidal points, are among the most recognizable crystal shapes in mineralogy. Quartz occurs in nearly every rock type and geologic setting, from granite pegmatites to sedimentary sandstones to hydrothermal veins.
About Smoky Quartz
Smoky quartz is a brown to black variety of quartz colored by natural irradiation. The national gem of Scotland, it ranges from light tan to nearly opaque black.
Quartz vs Smoky Quartz FAQ
Is Quartz the same as Smoky Quartz?
No. Both are quartz family, but they are distinct species with different hardness, streak or luster. Both sit near Mohs 7, so a scratch test alone will not separate them. Lean on luster, streak and heft instead.
How can you tell Quartz from Smoky Quartz?
Both sit near Mohs 7, so a scratch test alone will not separate them. Lean on luster, streak and heft instead. Hold a thin edge to the light: Quartz is Transparent to translucent, Smoky Quartz is transparent. They overlap in black, gray, and brown, but Quartz also comes in clear, purple, yellow, and pink.
Which is harder, Quartz or Smoky Quartz?
They are about equally hard, both near Mohs 7.
Which is more valuable, Quartz or Smoky Quartz?
Quartz is usually the more valuable of the two: a typical collector specimen runs about $35 against $30 for Smoky Quartz, and premium Quartz can reach $250 or more.
