Rhabdoborite-(W) is an exceptionally rare borate mineral found primarily in the contact-metasomatic boron deposits of the Tayozhnoye region in Russia. It typically occurs as small tabular crystals embedded within skarn mineral assemblages alongside magnetite and ludwigite. Collectors prize it for its restricted type locality and complex borate structure.

Hardness
5-6
Mohs
Luster
Vitreous
Streak
White
Transparency
Transparent

Is this rhabdoborite-(w)?

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 rhabdoborite-(w) with a known reference. Rhabdoborite-(W) sits at Mohs 5-6 — softer than the next harder reference, harder than the previous one.
  • 2
    Check the streak
    Drag the specimen across an unglazed porcelain plate. Rhabdoborite-(W) leaves a white streak.
  • 3
    Read the luster
    Hold the specimen under a strong light. Rhabdoborite-(W) typically shows a vitreous luster.
  • 4
    Match the color range
    Compare against the expected color range: colorless, white, yellow.
  • 5
    Look at form & habit
    Crystal system: trigonal. Typical habit: tabular crystals, subparallel aggregates.

Often confused with

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

Often found alongside rhabdoborite-(w)

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

All properties

Chemical formula
Mg₁₂Mg(PO₄)₂B₆O₁₀(OH,O)₈
Mohs hardness
5-6
Density
3.31 g/cm³
Streak
White
Luster
Vitreous
Transparency
Transparent
Crystal system
Trigonal
Crystal habit
Tabular Crystals, Subparallel Aggregates
Cleavage
None
Rarity
Rare
Uses
Collector
Host rock
Boron-rich Magnesium Skarns
Typical price
n/a

Where rockhounds find rhabdoborite-(w)

Classic worldwide localities

  • Tayozhnoye iron deposit, Yakutia, Russia

Field-hunting tip

Look in boron-rich magnesium skarns country — that is the host setting where rhabdoborite-(w) typically forms. If you start seeing ludwigite, forsterite, magnetite in float, you are in the right ground. Field specimens usually show a tabular crystals, subparallel aggregates habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify rhabdoborite-(w)?+
Mohs hardness is 5-6. It typically shows a vitreous luster. The streak is white. Common colors include colorless, white, yellow.
Where is rhabdoborite-(w) found?+
Notable localities include Tayozhnoye iron deposit, Yakutia, Russia.
How much is rhabdoborite-(w) worth?+
Typical asking prices fall in the range of n/a. Quality, size, and provenance can move individual specimens well outside that range.
What rocks look like rhabdoborite-(w)?+
Rhabdoborite-(W) is most often confused with Rhabdoborite-(V), Apatite. A quick hardness test and a streak check separate the look-alikes faster than color alone.
What minerals are found with rhabdoborite-(w)?+
Rhabdoborite-(W) commonly co-occurs with Ludwigite, Forsterite, Magnetite, Phlogopite. Spotting any of these in float or country rock is a useful trip signal.
What kind of rock does rhabdoborite-(w) form in?+
Rhabdoborite-(W) typically forms in boron-rich magnesium skarns. Working float back to the host body is the standard way to chase a fresh occurrence.
What is rhabdoborite-(w) used for?+
Rhabdoborite-(W) is used in collector.

Find rhabdoborite-(w) on the map

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