Adranosite-(Fe) is an extremely rare sulfate mineral found primarily in active volcanic fumaroles. It typically forms as small, distinct tabular crystals deposited by volcanic gases at high temperatures.

Hardness

2-3

Mohs

Luster

Vitreous

Streak

White

Transparency

Transparent

mineralrareAlunite Supergroup family

Adranosite-(Fe)

Hardness: 2-3
Luster: Vitreous
Streak: White
Transparency: Transparent

No image

Is this adranosite-(fe)?

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 adranosite-(fe) with a known reference. Adranosite-(Fe) sits at Mohs 2-3, softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Adranosite-(Fe) leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Adranosite-(Fe) typically shows a vitreous luster.
4
Match the color range
Compare against the expected color range: yellow, yellowish-orange.
5
Look at form & habit
Crystal system: tetragonal. Typical habit: tabular crystals.

Often confused with

Adranosite-(Fe) vs. its common look-alikes, and how to tell them apart in the field.

Often found alongside adranosite-(fe)

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

All properties

Chemical formula: (NH₄)₄NaFe₂(SO₄)₄Cl(OH)₂
Mohs hardness: 2-3
Density: 2.18 g/cm³
Colors: Yellow Yellowish-orange
Streak: White
Luster: Vitreous
Transparency: Transparent
Crystal system: Tetragonal
Crystal habit: Tabular Crystals
Cleavage: Present On {001}
Rarity: Rare
Uses: Collector
Host rock: Fumarolic Deposits

Where rockhounds find adranosite-(fe)

Classic worldwide localities

La Fossa crater, Vulcano, Aeolian Islands, Italy

Field-hunting tip

Look in fumarolic deposits country, the host setting where adranosite-(fe) typically forms. If you start seeing sulphur, gypsum, anhydrite in float, you are in the right ground. Field specimens usually show a tabular crystals habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify adranosite-(fe)?+

Mohs hardness is 2-3. It typically shows a vitreous luster. The streak is white. Common colors include yellow, yellowish-orange.

Where is adranosite-(fe) found?+

Notable localities include La Fossa crater, Vulcano, Aeolian Islands, Italy.

What rocks look like adranosite-(fe)?+

Adranosite-(Fe) is most often confused with Adranosite, Alunite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with adranosite-(fe)?+

Adranosite-(Fe) commonly co-occurs with Sulphur, Gypsum, Anhydrite, Hieratite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does adranosite-(fe) form in?+

Adranosite-(Fe) typically forms in fumarolic deposits. Working float back to the host body is the standard way to chase a fresh occurrence.

What is adranosite-(fe) used for?+

Adranosite-(Fe) is used in collector.

Find adranosite-(fe) on the map

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