Reidite is a high-pressure polymorph of zircon, formed exclusively under the extreme pressures generated by meteorite impacts. It is typically found as microscopic grains or intergrowths within shocked zircon crystals, making it a crucial mineral for planetary scientists studying impact events.
Is this reidite?
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 reidite with a known reference. Reidite sits at Mohs ~7.5, 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: adamantine.
- 4Match the color rangeCompare against the expected color range: white.
- 5Look at form & habitCrystal system: tetragonal. Typical habit: epitaxial, inclusions.
Often confused with
Reidite vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside reidite
Minerals reported to co-occur with reidite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- ZrSiO₄
- Mohs hardness
- ~7.5
- Density
- 4.6-4.7 g/cm³
- Colors
- Streak
- White
- Luster
- Adamantine
- Transparency
- Transparent
- Crystal system
- Tetragonal
- Crystal habit
- Epitaxial, inclusions
- Cleavage
- None
- Rarity
- Rare
- Uses
- Collector
- Host rock
- Epitaxially oriented in shock-metamorphosed zircons in an impact ejecta layer in marine sediment on the upper continental slope; detrital in clastic sedimentary rocks
Where rockhounds find reidite
Classic worldwide localities
- USA upper continental slope off New Jersey (Deep Sea Drilling Project Site 612, Hole 903C, and Hole 904A) and off Maryland ( Deep Sea Drilling Project Site 1073 Hole A)
- Vredefort impact structure (South Africa), Arctic Canada
- Meteor Crater, (Arizona) and Rock Elm impact crater (western Wisconsin), USA, Arctic Canada
- Haughton impact structure on Devon Island, Nunavut, Arctic Canada
- Stac Fada impactite, collected near Stac Fada sea stack, north side of the Bay of Stoer, Scotland
Field-hunting tip
Where it forms: Epitaxially oriented in shock-metamorphosed zircons in an impact ejecta layer in marine sediment on the upper continental slope; detrital in clastic sedimentary rocks. If you start seeing impact glass, coesite, stishovite in float, you are in the right ground. Typical habit: epitaxial, inclusions. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify reidite?+
Where is reidite found?+
What rocks look like reidite?+
What minerals are found with reidite?+
What kind of rock does reidite form in?+
What is reidite used for?+
Find reidite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
