Hendekasartorite is an extremely rare sulfosalt mineral primarily identified at the classic Lengenbach locality in Switzerland. It forms metallic, lead-gray prismatic crystals that are frequently confused with other arsenic-lead sulfosalts found in the same mineralized pockets. Collectors value it for its complex structural relationship within the Sartorite group and its limited geological occurrence.
Is this hendekasartorite?
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 hendekasartorite with a known reference. Hendekasartorite sits at Mohs 3-3.5, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Streak: dark brown.
- 3Read the lusterHold the specimen under a strong light. Luster: metallic.
- 4Match the color rangeCompare against the expected color range: lead-gray.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: prismatic, elongated crystals.
Often confused with
Hendekasartorite vs. its common look-alikes, and how to tell them apart in the field.
How to tell apart: Streak differs, so Hendekasartorite leaves dark brown, Sartorite leaves chocolate-brown.
How to tell apart: Streak differs, so Hendekasartorite leaves dark brown, Dufrénoysite leaves reddish brown to chocolate-brown; luster reads metallic on Hendekasartorite and submetallic on Dufrénoysite.
How to tell apart: Streak differs, so Hendekasartorite leaves dark brown, Gratonite leaves black.
Often found alongside hendekasartorite
Minerals reported to co-occur with hendekasartorite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Tl₂Pb₄₈As₈₂S₁₇₂
- Mohs hardness
- 3-3.5
- Density
- 5.18 g/cm³
- Colors
- Streak
- Dark brown
- Luster
- Metallic
- Transparency
- Opaque
- Crystal system
- Monoclinic
- Crystal habit
- Prismatic, elongated crystals
- Cleavage
- Good on {100}
- Rarity
- Rare
- Uses
- Collector
- Host rock
- In dolostone
Where rockhounds find hendekasartorite
Classic worldwide localities
- Lengenbach quarry, Binntal, Wallis, Switzerland
Field-hunting tip
Where it forms: In dolostone. If you start seeing baumhauerite, rathite in float, you are in the right ground. Typical habit: prismatic, elongated crystals. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify hendekasartorite?+
Where is hendekasartorite found?+
Is hendekasartorite safe to handle?+
What rocks look like hendekasartorite?+
What minerals are found with hendekasartorite?+
What kind of rock does hendekasartorite form in?+
What is hendekasartorite used for?+
Find hendekasartorite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
