Hawleyite is a rare, bright yellow cadmium sulfide mineral that typically occurs as a powdery coating on other minerals like sphalerite. It is chemically identical to greenockite but forms in a cubic crystal system, distinguishing it as a distinct mineral species.
Is this hawleyite?
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 hawleyite with a known reference. Hawleyite sits at Mohs 2.5-3, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Streak: light yellow.
- 3Read the lusterHold the specimen under a strong light. Luster: metallic.
- 4Match the color rangeCompare against the expected color range: light yellow.
- 5Look at form & habitCrystal system: cubic. Typical habit: powdery coatings.
Often confused with
Hawleyite vs. its common look-alikes, and how to tell them apart in the field.
How to tell apart: Streak differs, so Hawleyite leaves light yellow, Greenockite leaves yellow-orange to brick-red; luster reads metallic on Hawleyite and adamantine to resinous on Greenockite.
How to tell apart: Streak differs, so Hawleyite leaves light yellow, Sulfur leaves white; luster reads metallic on Hawleyite and resinous on Sulfur.
Often found alongside hawleyite
Minerals reported to co-occur with hawleyite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- CdS
- Mohs hardness
- 2.5-3
- Density
- 4.87 g/cm³
- Colors
- Streak
- Light yellow
- Luster
- Metallic
- Transparency
- Opaque to subtranslucent
- Crystal system
- Cubic
- Crystal habit
- Powdery coatings
- Cleavage
- None
- Rarity
- Rare
- Uses
- Collector
- Host rock
- As coatings on fine-grained sphalerite and siderite in vugs; probably of secondary origin, deposited from meteoric waters in vugs and along late fractures
Where rockhounds find hawleyite
Classic worldwide localities
- Hanover, Grant Co., New Mexico, USA
- Crestmore quarry, Riverside Co., California, USA
- Bethel Church, Pike Co., Indiana, USA
- Franklin, Sussex Co., New Jersey, USA
- Hector-Calumet mine, Keno-Galena Hill area, Yukon Territory (type locality), and in the Strathcona mine, Sudbury, Ontario, Canada
- Komna, Czech Republic
Field-hunting tip
Where it forms: As coatings on fine-grained sphalerite and siderite in vugs; probably of secondary origin, deposited from meteoric waters in vugs and along late fractures. If you start seeing sphalerite, siderite, greenockite in float, you are in the right ground. Typical habit: powdery coatings. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify hawleyite?+
Where is hawleyite found?+
Is hawleyite safe to handle?+
What rocks look like hawleyite?+
What minerals are found with hawleyite?+
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Find hawleyite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
