Ringwoodite is a high-pressure polymorph of olivine that exists deep within the Earth's mantle transition zone between 520 and 660 kilometers deep. Because it is rarely brought to the surface except via meteorites or as rare inclusions in deep-seated diamonds, it is an exceptionally rare find for collectors and scientists alike.
Is this ringwoodite?
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 ringwoodite with a known reference. Ringwoodite sits at Mohs 6.5-7, 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: blue gray, colorless, light violet, purple, smoky gray.
- 5Look at form & habitCrystal system: cubic. Typical habit: anhedral grains, microscopic crystals.
Often confused with
Ringwoodite vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside ringwoodite
Minerals reported to co-occur with ringwoodite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Mg₂SiO₄
- Mohs hardness
- 6.5-7
- Density
- 3.9 g/cm³
- Colors
- Streak
- White
- Luster
- Vitreous
- Transparency
- Semitransparent
- Crystal system
- Cubic
- Crystal habit
- Anhedral grains, microscopic crystals
- Cleavage
- None
- Rarity
- Rare
- Uses
- Collector, Scientific research
- Host rock
- In veinlets cutting the matrix of meteorites and replacing olivine; probably produced during shock metamorphism
Where rockhounds find ringwoodite
Classic worldwide localities
- Tenham, Pampa del Infierno, Catherwood, and Coorara chondrite meteorites
Field-hunting tip
Where it forms: In veinlets cutting the matrix of meteorites and replacing olivine; probably produced during shock metamorphism. If you start seeing majorite, magnesian silicate glass in float, you are in the right ground. Typical habit: anhedral grains, microscopic crystals. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify ringwoodite?+
Where is ringwoodite found?+
What rocks look like ringwoodite?+
What minerals are found with ringwoodite?+
What kind of rock does ringwoodite form in?+
What is ringwoodite used for?+
Find ringwoodite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
