Argentopyrite is a rare silver iron sulfide that typically forms thin, tabular, pseudo-hexagonal crystals often found intergrown with sternbergite. It is primarily identified by its distinct metallic luster and association with other silver-bearing sulfides in hydrothermal vein deposits. Due to its scarcity and similarity to other silver minerals, it is highly sought after by advanced systematic collectors.
Is this argentopyrite?
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 argentopyrite with a known reference. Argentopyrite sits at Mohs 3.5-4, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Streak: gray.
- 3Read the lusterHold the specimen under a strong light. Luster: metallic.
- 4Match the color rangeCompare against the expected color range: blue, bronze brown, green, yellow, white.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: tabular crystals, sometimes in pseudo-hexagonal groups or twins.
Often confused with
Argentopyrite vs. its common look-alikes, and how to tell them apart in the field.
How to tell apart: Argentopyrite is noticeably harder (Mohs 3.5-4 vs. 1-1.5); streak differs, so Argentopyrite leaves gray, Sternbergite leaves black.
How to tell apart: Streak differs, so Argentopyrite leaves gray, Pyrrhotite leaves dark grayish black.
How to tell apart: Arsenopyrite is the harder of the two (Mohs 5.5-6 vs. 3.5-4); streak differs, so Argentopyrite leaves gray, Arsenopyrite leaves black.
Often found alongside argentopyrite
Minerals reported to co-occur with argentopyrite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- AgFe₂S₃
- Mohs hardness
- 3.5-4
- Density
- 4.25 g/cm³
- Streak
- Gray
- Luster
- Metallic
- Transparency
- Opaque
- Crystal system
- Monoclinic
- Crystal habit
- Tabular crystals, sometimes in pseudo-hexagonal groups or twins
- Cleavage
- None
- Rarity
- Rare
- Uses
- Collector, Scientific study
- Host rock
- Rare in silver-bearing hydrothermal veins
Where rockhounds find argentopyrite
Classic worldwide localities
- Jáchymov (Joachimsthal) (type locality), Příbram, and in the Krušné hory Mountains, at Měděnec, Czech Republic
- St. Andreasberg, Harz Mountains, Germany
- Marienberg, Schneeberg, Johanngeorgenstadt, and Freiberg, Saxony, Germany
- Anton mine, Wieden, Black Forest, Germany
- Tynebottom mine, Garrigill, near Alston, Cumbria, England
- Broken Hill, New South Wales, Australia
Field-hunting tip
Where it forms: Rare in silver-bearing hydrothermal veins. If you start seeing arsenic, proustite, pyrargyrite in float, you are in the right ground. Typical habit: tabular crystals, sometimes in pseudo-hexagonal groups or twins. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify argentopyrite?+
Where is argentopyrite found?+
Is argentopyrite safe to handle?+
What rocks look like argentopyrite?+
What minerals are found with argentopyrite?+
What kind of rock does argentopyrite form in?+
What is argentopyrite used for?+
Find argentopyrite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
