Raw Stones
180 pieces
Tumbled Stones
162 pieces
Palm Stones
26 pieces
Crystal Points
23 pieces
Clusters & Geodes
112 pieces
Polished & Decor
155 pieces
Mineral Specimens
268 collector pieces
Crystal Chips
21 pieces
Browse everything
Every collection, one page.
View All Collections →
Aries
Mar 21 – Apr 19
Carnelian
›
Taurus
Apr 20 – May 20
Rose Quartz
›
Gemini
May 21 – Jun 20
Agate
›
Cancer
Jun 21 – Jul 22
Moonstone
›
Leo
Jul 23 – Aug 22
Citrine
›
Virgo
Aug 23 – Sep 22
Amazonite
›
Libra
Sep 23 – Oct 22
Blue Lace Agate
›
Scorpio
Oct 23 – Nov 21
Obsidian
›
Sagittarius
Nov 22 – Dec 21
Sodalite
›
Capricorn
Dec 22 – Jan 19
Black Tourmaline
›
Aquarius
Jan 20 – Feb 18
Amethyst
›
Pisces
Feb 19 – Mar 20
Aquamarine
›
Gifting?
A birthday stone is the safe bet.
Read the zodiac guide →
Chalcopyrite
Chalcopyrite is sulfide (copper iron), CuFeS₂. In the hand, it rates 3.5 to 4 on the Mohs scale, and it runs brass yellow and golden. Deeper brass-gold than pyrite and soft enough for a knife to scratch, often sold rainbow-tarnished as 'peacock ore'. The world's most important copper ore; notable: Mexico, Peru, China, Missouri (USA).
The geology.
Chalcopyrite carries the formula CuFeS₂. It belongs to the tetragonal system. On paper it is sulfide (copper iron).
It sits at 3.5 to 4 on the Mohs scale. The surface reads metallic. Light behaviour is opaque. Specific gravity runs 4.1 to 4.3. The streak is greenish black. It breaks with uneven fracture; brittle.
Deeper brass-gold than pyrite and soft enough for a knife to scratch, often sold rainbow-tarnished as 'peacock ore'.
Expect to see it as raw chunks, massive ore or acid-treated 'peacock ore'.
The origins.
The world's most important copper ore; notable: Mexico, Peru, China, Missouri (USA).
On value, the database notes: common and affordable.
Traditional associations.
In energy work traditions, associated with abundance and uplift.
Recorded here because it is part of how this material is sold, not because it is a property of the material.
Spotting the real thing.
Deeper brass-gold than pyrite and soft enough for a knife to scratch, often sold rainbow-tarnished as 'peacock ore'.
Sold as 'bornite/peacock ore' after acid treatment, mislabeled, though the mineral itself is genuine.
| Looks like | How to tell them apart |
|---|---|
| Pyrite | Pyrite is paler brass and harder (6 to 6.5), a knife won't scratch it |
| Gold | Gold is malleable and dents; chalcopyrite shatters |
| Bornite | True bornite shows bronze under its purple tarnish; chalcopyrite shows brass yellow |
At-home tests.
None of these need a lab. A 10x loupe, good daylight and a steady hand cover most of what a buyer needs to know about chalcopyrite.
| Test | What you should see |
|---|---|
| Scratch check | Knife scratches it (Mohs 3.5 to 4) |
| By eye | Greenish-black streak |
| By eye | Heavy in hand (SG ~4.2) |
Anything that scratches, burns or dissolves the piece is a lab job. Get it appraised rather than testing it apart.
Care & handling.
At 3.5 to 4 on the Mohs scale this is a soft material. Keep it as a display piece, store it apart from harder stones, and skip daily-wear settings.
It breaks with uneven fracture; brittle, which is worth knowing before you set it or drop it.
Warm water and a soft cloth clean almost everything. Ultrasonic tanks, steamers and household cleaners are where pieces get ruined.
Copper-iron sulfide, wash hands after handling crumbly pieces.
A deeper look.
Extended detail on composition, sourcing, authentication and market value.
The physical record
The formula on record is CuFeS₂. Crystal system: Tetragonal. Specific gravity: 4.1 to 4.3. Streak: Greenish black. Cleavage and fracture: Uneven fracture; brittle.
How it reaches the market
The world's most important copper ore; notable: Mexico, Peru, China, Missouri (USA).
What it gets confused with
Pyrite: Pyrite is paler brass and harder (6 to 6.5), a knife won't scratch it. Gold: Gold is malleable and dents; chalcopyrite shatters. Bornite: True bornite shows bronze under its purple tarnish; chalcopyrite shows brass yellow.
What it is worth
Common and affordable.
Where buyers get caught
Sold as 'bornite/peacock ore' after acid treatment, mislabeled, though the mineral itself is genuine.
One more thing
Nearly all vivid rainbow 'peacock ore' in shops is chalcopyrite given a quick acid bath to force the tarnish.
An education-first guide.
No product links here. We do not sell chalcopyrite, and a guide that only covers our own shelves would not be much of a guide.
Explore the Crystal GuideThe Slow Note
New stones go to the list first.
No forwarding, no selling. Unsubscribe in one click. Privacy