Diopside is a common rock-forming pyroxene mineral that frequently appears in contact-metamorphosed limestones. Collectors look for its characteristic prismatic, often square-sectioned crystals and distinctive green hues, with the deep 'chrome-diopside' variety being especially prized for its vivid color.
Is this diopside?
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 diopside with a known reference. Diopside sits at Mohs 5.5-6.5 — softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Diopside leaves a white streak.
- 3Read the lusterHold the specimen under a strong light. Diopside typically shows a vitreous luster.
- 4Match the color rangeCompare against the expected color range: white, gray, green, yellow-green, dark green, black.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: prismatic crystals, granular, massive.
Often confused with
Diopside vs. its common look-alikes — and how to tell them apart in the field.
Often found alongside diopside
Minerals reported to co-occur with diopside. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- CaMgSi₂O₆
- Mohs hardness
- 5.5-6.5
- Density
- 3.22-3.38 g/cm³
- Streak
- White
- Luster
- Vitreous
- Transparency
- Translucent
- Crystal system
- Monoclinic
- Crystal habit
- Prismatic Crystals, Granular, Massive
- Cleavage
- Good Prismatic At 87 and 93 Degrees
- Rarity
- Common
- Uses
- Collector, Gemstone, Lapidary
- Host rock
- Contact Metamorphosed Limestone and Dolomite
- Typical price
- $5-50 for small specimens, $100+ for large gem-quality crystals or chrome-diopside specimens
Where rockhounds find diopside
24 mapped spotsClassic worldwide localities
- Italy
- Canada
- Russia
- USA
- Madagascar
- Pakistan
U.S. states with diopside
Each link opens a state-specific list of mapped rockhounding spots that produce diopside.
Field-hunting tip
Look in contact metamorphosed limestone and dolomite country — that is the host setting where diopside typically forms. If you start seeing calcite, forsterite, grossular in float, you are in the right ground. Field specimens usually show a prismatic crystals, granular, massive habit, so train your eye for that shape before scanning the outcrop. In the U.S., the densest reported localities are in Utah, New York, Vermont — start trip planning there.
Common questions
How do you identify diopside?+
Where is diopside found?+
Can I find diopside in the United States?+
How much is diopside worth?+
What rocks look like diopside?+
What minerals are found with diopside?+
What kind of rock does diopside form in?+
What is diopside used for?+
Find diopside on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
