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George-ericksenite is a very rare hydrated sodium-manganese-chromium arsenate mineral known primarily from the Chuquicamata mine in Chile. Collectors look for its characteristic pale yellow, radiating acicular crystal sprays found in sulfate-rich oxidized mineral assemblages.

Hardness
3-4
Mohs
Luster
Vitreous
Streak
Pale yellow
Transparency
Transparent to translucent

Is this george-ericksenite?

5-step field check

Run through these checks against the specimen in your hand. The more boxes tick, the more confident the ID.

  • 1
    Test the hardness
    Try to scratch george-ericksenite with a known reference. George-ericksenite sits at Mohs 3-4, softer than the next harder reference, harder than the previous one.
  • 2
    Check the streak
    Drag the specimen across an unglazed porcelain plate. Streak: pale yellow.
  • 3
    Read the luster
    Hold the specimen under a strong light. Luster: vitreous.
  • 4
    Match the color range
    Compare against the expected color range: pale yellow, bright lemon yellow.
  • 5
    Look at form & habit
    Crystal system: monoclinic. Typical habit: acicular, prismatic.

Often confused with

George-ericksenite vs. its common look-alikes, and how to tell them apart in the field.

Allactite mineral
mineral
Allactite
Mohs 4.5

How to tell apart: Streak differs, so George-ericksenite leaves pale yellow, Allactite leaves gray to faint brown.

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No image
mineral
Flinkite
Mohs 4.5

How to tell apart: Streak differs, so George-ericksenite leaves pale yellow, Flinkite leaves light brown.

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Often found alongside george-ericksenite

Minerals reported to co-occur with george-ericksenite. Spotting these in float or country rock is a strong cue you are in the right ground.

All properties

Chemical formula
Na₆CaMg(IO₃)₆(CrO₄)₂·12H₂O
Mohs hardness
3-4
Density
3.035 g/cm³
Colors
Pale yellowBright lemon yellow
Streak
Pale yellow
Luster
Vitreous
Transparency
Transparent to translucent
Crystal system
Monoclinic
Crystal habit
Acicular, prismatic
Cleavage
None
Rarity
Rare
Uses
Collector
Host rock
On a museum specimen from a nitrate deposit

Where rockhounds find george-ericksenite

Classic worldwide localities

  • Oficina Chacabuco, Taltal district, Antofagasta, Chile

Field-hunting tip

Where it forms: On a museum specimen from a nitrate deposit. If you start seeing halite, nitratine, niter in float, you are in the right ground. Typical habit: acicular, prismatic. Train your eye for that shape before scanning the outcrop.

Common questions

How do you identify george-ericksenite?+
Mohs hardness is 3-4. Luster: vitreous. The streak is pale yellow. Common colors include pale yellow, bright lemon yellow.
Where is george-ericksenite found?+
Notable localities include Oficina Chacabuco, Taltal district, Antofagasta, Chile.
Is george-ericksenite safe to handle?+
George-ericksenite contains hexavalent chromium and calls for real care. Contains arsenic, a toxic element. Handle with care, wash hands after touching, and avoid inhaling dust or powder.
What rocks look like george-ericksenite?+
George-ericksenite is most often confused with Allactite, Flinkite. A quick hardness test and a streak check separate the look-alikes faster than color alone.
What minerals are found with george-ericksenite?+
George-ericksenite commonly co-occurs with Halite, Nitratine, Niter. Spotting any of these in float or country rock is a useful trip signal.
What kind of rock does george-ericksenite form in?+
Where it forms: On a museum specimen from a nitrate deposit. Working float back to the host body is the standard way to chase a fresh occurrence.
What is george-ericksenite used for?+
George-ericksenite is used in collector.

Find george-ericksenite on the map

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