Ardennite-(V) is a rare manganese-vanadium sorosilicate mineral that typically forms as prismatic to acicular crystals within manganese deposits. It is most recognized for its distinct yellow-brown color and its association with other manganese-rich silicate minerals in metamorphosed sedimentary environments.

Hardness

6-7

Mohs

Luster

Vitreous

Streak

White

Transparency

Translucent

mineralrareArdennite Group family

Ardennite-(V)

Hardness: 6-7
Luster: Vitreous
Streak: White
Transparency: Translucent

Is this ardennite-(v)?

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 ardennite-(v) with a known reference. Ardennite-(V) sits at Mohs 6-7 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Ardennite-(V) leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Ardennite-(V) typically shows a vitreous luster.
4
Match the color range
Compare against the expected color range: yellow, brown, reddish-brown.
5
Look at form & habit
Crystal system: orthorhombic. Typical habit: prismatic crystals, radiating aggregates.

Often confused with

Ardennite-(V) vs. its common look-alikes — and how to tell them apart in the field.

Often found alongside ardennite-(v)

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

All properties

Chemical formula: (Mn²⁺,Ca)₄(Al,Mg,Fe³⁺,V⁵⁺)₆(SiO₄)₂(Si₂O₇)(AsO₄,SiO₄)(OH,O)₆
Mohs hardness: 6-7
Density: 3.62 g/cm³
Colors: Yellow Brown Reddish-brown
Streak: White
Luster: Vitreous
Transparency: Translucent
Crystal system: Orthorhombic
Crystal habit: Prismatic Crystals, Radiating Aggregates
Cleavage: Good
Rarity: Rare
Uses: Collector
Host rock: Manganese-rich Metamorphic Rocks
Typical price: $50-500 depending on specimen quality and rarity

Where rockhounds find ardennite-(v)

Classic worldwide localities

Ardennes, Belgium
Val Graveglia, Italy
Hibernia Mine, New Jersey, USA

Field-hunting tip

Look in manganese-rich metamorphic rocks country — that is the host setting where ardennite-(v) typically forms. If you start seeing quartz, spessartine, braunite in float, you are in the right ground. Field specimens usually show a prismatic crystals, radiating aggregates habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify ardennite-(v)?+

Mohs hardness is 6-7. It typically shows a vitreous luster. The streak is white. Common colors include yellow, brown, reddish-brown.

Where is ardennite-(v) found?+

Notable localities include Ardennes, Belgium; Val Graveglia, Italy; Hibernia Mine, New Jersey, USA.

How much is ardennite-(v) worth?+

Typical asking prices fall in the range of $50-500 depending on specimen quality and rarity. Quality, size, and provenance can move individual specimens well outside that range.

Is ardennite-(v) safe to handle?+

It contains toxic constituents. Contains arsenic, which is toxic; wash hands thoroughly after handling and avoid inhaling dust during preparation or cleaning. Handle with care, avoid grinding or breathing dust, and store separately.

What rocks look like ardennite-(v)?+

Ardennite-(V) is most often confused with Epidote, Clinozoisite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with ardennite-(v)?+

Ardennite-(V) commonly co-occurs with Quartz, Spessartine, Braunite, Hematite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does ardennite-(v) form in?+

Ardennite-(V) typically forms in manganese-rich metamorphic rocks. Working float back to the host body is the standard way to chase a fresh occurrence.

What is ardennite-(v) used for?+

Ardennite-(V) is used in collector.

Find ardennite-(v) on the map

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