Smoky Quartz is a variety of quartz that ranges in color from light smoky gray to deep brownish-black due to natural irradiation of aluminum impurities within the crystal structure. It is highly prized by collectors for its sharp, well-terminated prismatic crystals often found in granitic pegmatites and alpine-type fissures.
Is this smoky quartz?
5-step field checkRun through these checks against the specimen in your hand. The more boxes tick, the more confident the ID.
- 1Test the hardnessTry to scratch smoky quartz with a known reference. Smoky Quartz sits at Mohs 7 — softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Smoky Quartz leaves a white streak.
- 3Read the lusterHold the specimen under a strong light. Smoky Quartz typically shows a vitreous luster.
- 4Match the color rangeCompare against the expected color range: brown, gray, black, smoky.
- 5Look at form & habitCrystal system: trigonal. Typical habit: prismatic crystals.
Often confused with
Smoky Quartz vs. its common look-alikes — and how to tell them apart in the field.
Often found alongside smoky quartz
Minerals reported to co-occur with smoky quartz. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- SiO₂
- Mohs hardness
- 7
- Density
- 2.65 g/cm³
- Streak
- White
- Luster
- Vitreous
- Transparency
- Transparent
- Crystal system
- Trigonal
- Crystal habit
- Prismatic Crystals
- Cleavage
- None
- Rarity
- Common
- Uses
- Collector, Lapidary, Gemstone
- Host rock
- Pegmatites, Granites, And Hydrothermal Veins
- Typical price
- $10-100 per specimen
Where rockhounds find smoky quartz
70 mapped spotsClassic worldwide localities
- Brazil
- Scotland
- Switzerland
- USA
- Madagascar
U.S. states with smoky quartz
Each link opens a state-specific list of mapped rockhounding spots that produce smoky quartz.
Field-hunting tip
Look in pegmatites, granites, and hydrothermal veins country — that is the host setting where smoky quartz typically forms. If you start seeing microcline, albite, muscovite in float, you are in the right ground. Field specimens usually show a prismatic crystals habit, so train your eye for that shape before scanning the outcrop. In the U.S., the densest reported localities are in North Carolina, New Hampshire, South Carolina — start trip planning there.
Common questions
How do you identify smoky quartz?+
Where is smoky quartz found?+
Can I find smoky quartz in the United States?+
How much is smoky quartz worth?+
What rocks look like smoky quartz?+
What minerals are found with smoky quartz?+
What kind of rock does smoky quartz form in?+
What is smoky quartz used for?+
Find smoky quartz on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
