Bambollaite is an extremely rare copper selenium oxysalt mineral that occurs as small, dark blue, platy crystals. It is primarily found in the oxidized zones of selenium-rich hydrothermal deposits, most notably at its type locality in Sonora, Mexico.
Is this bambollaite?
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 bambollaite with a known reference. Bambollaite sits at Mohs 2 — softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Bambollaite leaves a blue streak.
- 3Read the lusterHold the specimen under a strong light. Bambollaite typically shows a submetallic luster.
- 4Match the color rangeCompare against the expected color range: dark blue, black.
- 5Look at form & habitCrystal system: tetragonal. Typical habit: platy crystals, granular aggregates.
Often confused with
Bambollaite vs. its common look-alikes — and how to tell them apart in the field.
How to tell apart: Streak differs — Bambollaite leaves blue, Chalcomenite leaves pale blue; luster reads submetallic on Bambollaite and vitreous on Chalcomenite.
How to tell apart: Streak differs — Bambollaite leaves blue, Ahlfeldite leaves pinkish-white; luster reads submetallic on Bambollaite and vitreous on Ahlfeldite.
Often found alongside bambollaite
Minerals reported to co-occur with bambollaite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Cu₄SeO₃(OH)₆
- Mohs hardness
- 2
- Density
- 4.2 g/cm³
- Streak
- Blue
- Luster
- Submetallic
- Transparency
- Opaque
- Crystal system
- Tetragonal
- Crystal habit
- Platy Crystals, Granular Aggregates
- Cleavage
- Perfect
- Rarity
- Rare
- Uses
- Collector
- Host rock
- Oxidized Hydrothermal Selenium Deposits
- Typical price
- $50-300 per specimen
Where rockhounds find bambollaite
Classic worldwide localities
- Bambolla Mine, Moctezuma, Sonora, Mexico
Field-hunting tip
Look in oxidized hydrothermal selenium deposits country — that is the host setting where bambollaite typically forms. If you start seeing chalcomenite, quetzalcoatlite, moctezumite in float, you are in the right ground. Field specimens usually show a platy crystals, granular aggregates habit, so train your eye for that shape before scanning the outcrop.
Common questions
How do you identify bambollaite?+
Where is bambollaite found?+
How much is bambollaite worth?+
Is bambollaite safe to handle?+
What rocks look like bambollaite?+
What minerals are found with bambollaite?+
What kind of rock does bambollaite form in?+
What is bambollaite used for?+
Find bambollaite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
