Moctezumite is an exceptionally rare lead tellurite mineral discovered in the oxidized zones of tellurium-rich ore deposits. It is best known from its type locality in Sonora, Mexico, typically forming distinct, vibrant orange to red platy crystals or thin crusts on matrix. Due to its extreme rarity and specific geochemical requirements, it is a highly sought-after prize for advanced mineral collectors.
Is this moctezumite?
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 moctezumite with a known reference. Moctezumite sits at Mohs ~3, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Streak: yellow-orange.
- 3Read the lusterHold the specimen under a strong light. Luster: dull.
- 4Match the color rangeCompare against the expected color range: orange, dark orange, brownish orange.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: platy crystals, radial aggregates, crusts.
Often confused with
Moctezumite vs. its common look-alikes, and how to tell them apart in the field.
How to tell apart: Ecandrewsite is the harder of the two (Mohs 5-5.5 vs. ~3); streak differs, so Moctezumite leaves yellow-orange, Ecandrewsite leaves dark brown to black; luster reads dull on Moctezumite and submetallic on Ecandrewsite.
How to tell apart: Moctezumite is noticeably harder (Mohs ~3 vs. 2); streak differs, so Moctezumite leaves yellow-orange, Tellurite leaves white; luster reads dull on Moctezumite and subadamantine on Tellurite.
Often found alongside moctezumite
Minerals reported to co-occur with moctezumite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Pb(UO₂)(TeO₃)₂
- Mohs hardness
- ~3
- Density
- 5.73 g/cm³
- Colors
- Streak
- Yellow-orange
- Luster
- Dull
- Transparency
- Semitransparent
- Crystal system
- Monoclinic
- Crystal habit
- Platy crystals, radial aggregates, crusts
- Cleavage
- On {100}, perfect
- Rarity
- Rare
- Uses
- Collector
- Host rock
- A rare secondary mineral in the oxidized zone of a hydrothermal Au–Te deposit
Where rockhounds find moctezumite
Classic worldwide localities
- Moctezuma (Bambolla) mine, 12 km south of Moctezuma, Sonora, Mexico
Field-hunting tip
Where it forms: A rare secondary mineral in the oxidized zone of a hydrothermal Au–Te deposit. If you start seeing schmitterite, burckhardtite, zemannite in float, you are in the right ground. Typical habit: platy crystals, radial aggregates, crusts. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify moctezumite?+
Where is moctezumite found?+
Is moctezumite safe to handle?+
What rocks look like moctezumite?+
What minerals are found with moctezumite?+
What kind of rock does moctezumite form in?+
What is moctezumite used for?+
Find moctezumite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
