Monteponite is a rare cadmium oxide mineral that typically occurs as small, yellow to brown coatings or crusts in oxidized lead-zinc ore bodies. Due to its scarcity and association with cadmium, it is a significant find for mineral collectors focusing on rare species. It is most famous for its occurrence at the Monteponi Mine in Sardinia, Italy.
Is this monteponite?
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 monteponite with a known reference. Monteponite 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. Monteponite leaves a yellow streak.
- 3Read the lusterHold the specimen under a strong light. Monteponite typically shows a adamantine luster.
- 4Match the color rangeCompare against the expected color range: yellow, yellowish-brown, black.
- 5Look at form & habitCrystal system: cubic. Typical habit: massive, encrustations, or microscopic grains.
Often confused with
Monteponite vs. its common look-alikes — and how to tell them apart in the field.
How to tell apart: Streak differs — Monteponite leaves yellow, Otavite leaves white.
How to tell apart: Streak differs — Monteponite leaves yellow, Greenockite leaves brick-red to orange-yellow; luster reads adamantine on Monteponite and adamantine to resinous on Greenockite.
Often found alongside monteponite
Minerals reported to co-occur with monteponite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- CdO
- Mohs hardness
- 3
- Density
- 6.4 g/cm³
- Streak
- Yellow
- Luster
- Adamantine
- Transparency
- Opaque
- Crystal system
- Cubic
- Crystal habit
- Massive, Encrustations, Or Microscopic Grains
- Cleavage
- None
- Rarity
- Rare
- Uses
- Collector
- Host rock
- Oxidized Zones of Lead-zinc Deposits
- Typical price
- $50-300 per specimen
Where rockhounds find monteponite
Classic worldwide localities
- Monteponi Mine, Italy
- Tsumeb, Namibia
- Broken Hill, Australia
Field-hunting tip
Look in oxidized zones of lead-zinc deposits country — that is the host setting where monteponite typically forms. If you start seeing smithsonite, cerussite, calamine in float, you are in the right ground. Field specimens usually show a massive, encrustations, or microscopic grains habit, so train your eye for that shape before scanning the outcrop.
Common questions
How do you identify monteponite?+
Where is monteponite found?+
How much is monteponite worth?+
Is monteponite safe to handle?+
What rocks look like monteponite?+
What minerals are found with monteponite?+
What kind of rock does monteponite form in?+
What is monteponite used for?+
Find monteponite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
