Swaknoite is an extremely rare phosphate mineral typically found in guano-rich environments. It usually forms as small, colorless, acicular crystals associated with other phosphate minerals in cave deposits.

Hardness

1.5-2

Mohs

Luster

Vitreous

Streak

White

Transparency

Semitransparent

mineralrare

Swaknoite

Hardness: 1.5-2
Luster: Vitreous
Streak: White
Transparency: Semitransparent

No image

Is this swaknoite?

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 swaknoite with a known reference. Swaknoite sits at Mohs 1.5-2, softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Streak: white.
3
Read the luster
Hold the specimen under a strong light. Luster: vitreous.
4
Match the color range
Compare against the expected color range: white.
5
Look at form & habit
Crystal system: orthorhombic. Typical habit: acicular, rosette.

Often confused with

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

Often found alongside swaknoite

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

All properties

Chemical formula: Ca(NH₄)₂(HPO₄)₂·H₂O
Mohs hardness: 1.5-2
Density: 1.91 g/cm³
Colors: White
Streak: White
Luster: Vitreous
Transparency: Semitransparent
Crystal system: Orthorhombic
Crystal habit: Acicular, rosette
Cleavage: None
Rarity: Rare
Uses: Collector
Host rock: Formed from bat guano and urine by reaction with cave walls

Where rockhounds find swaknoite

Classic worldwide localities

Found in Arnhem Cave, 150 km east of Windhoek, Namibia

Field-hunting tip

Where it forms: Formed from bat guano and urine by reaction with cave walls. If you start seeing mundrabillaite, dittmarite, arcanite in float, you are in the right ground. Typical habit: acicular, rosette. Train your eye for that shape before scanning the outcrop.

Common questions

How do you identify swaknoite?+

Mohs hardness is 1.5-2. Luster: vitreous. The streak is white. Common colors include white.

Where is swaknoite found?+

Notable localities include Found in Arnhem Cave, 150 km east of Windhoek, Namibia.

What rocks look like swaknoite?+

Swaknoite is most often confused with Hannayite, Stercorite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with swaknoite?+

Swaknoite commonly co-occurs with Mundrabillaite, Dittmarite, Arcanite, Dolomite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does swaknoite form in?+

Where it forms: Formed from bat guano and urine by reaction with cave walls. Working float back to the host body is the standard way to chase a fresh occurrence.

What is swaknoite used for?+

Swaknoite is used in collector.

Find swaknoite on the map

RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.