Prase is a leek-green variety of quartz colored by inclusions of actinolite or hedenbergite. It is often distinguished from chrysoprase by its darker, olive-green hue and typically occurs in granular or massive crystalline aggregates.
Is this prase?
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 prase with a known reference. Prase 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. Streak: white.
- 3Read the lusterHold the specimen under a strong light. Luster: vitreous.
- 4Match the color rangeCompare against the expected color range: leek-green, olive-green.
- 5Look at form & habitCrystal system: trigonal. Typical habit: massive, crystalline clusters, prismatic crystals.
Often confused with
Prase vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside prase
Minerals reported to co-occur with prase. 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
- Colors
- Leek-greenOlive-green
- Streak
- White
- Luster
- Vitreous
- Transparency
- Translucent
- Crystal system
- Trigonal
- Crystal habit
- Massive, crystalline clusters, prismatic crystals
- Cleavage
- None
- Rarity
- Uncommon
- Uses
- Collector, Lapidary, Ornamental
- Host rock
- hydrothermal veins, contact metamorphic rocks
Where rockhounds find prase
1 mapped spotsClassic worldwide localities
- Greece
- Finland
- Brazil
- USA
Field-hunting tip
Where it forms: hydrothermal veins, contact metamorphic rocks. If you start seeing quartz, calcite, magnetite in float, you are in the right ground. Typical habit: massive, crystalline clusters, prismatic crystals. Train your eye for that shape before scanning the outcrop. In the U.S., the densest reported localities are in Oregon. Start trip planning there.
Common questions
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Find prase on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
