Paulingite-K is a rare and complex zeolite mineral known for its distinctive rhombic dodecahedral crystal habit. It is typically found lining cavities in basaltic rocks and requires magnification to appreciate its intricate geometric forms.

Hardness

Mohs

Luster

Vitreous

Streak

White

Transparency

Transparent

mineralrareZeolite Group family

Paulingite-K

Hardness: ~5
Luster: Vitreous
Streak: White
Transparency: Transparent

Is this paulingite-k?

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 paulingite-k with a known reference. Paulingite-K sits at Mohs ~5, 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: colorless, light yellow, orange, red.
5
Look at form & habit
Crystal system: cubic. Typical habit: euhedral crystals.

Often confused with

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

Often found alongside paulingite-k

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

All properties

Chemical formula: (K,Ca,Na,Ba)₁₀(Si,Al)₄₂O₈₄·34H₂O
Mohs hardness: ~5
Density: 2.085 g/cm³
Colors: Colorless Light yellow Orange Red
Streak: White
Luster: Vitreous
Transparency: Transparent
Crystal system: Cubic
Crystal habit: Euhedral crystals
Cleavage: None
Rarity: Rare
Uses: Collector
Host rock: In vesicles in basalt flows

Where rockhounds find paulingite-k

Classic worldwide localities

Rock Island Dam, on the Columbia River, Wenatchee, Douglas Co., Washington, USA
Riggins, Idaho Co., USA
Three Mile Creek, near Ritter, Grant Co., Oregon, USA
Chase Creek, at the junction with Charcoal Creek, north of Falkland, British Columbia, Canada
Giant's Causeway and Craigahulliar, Portrush, Co. Antrim, Ireland
Kladno and Vinařice, Czech Republic

Field-hunting tip

Where it forms: In vesicles in basalt flows. If you start seeing zeolites, pyrite, calcite in float, you are in the right ground. Typical habit: euhedral crystals. Train your eye for that shape before scanning the outcrop.

Common questions

How do you identify paulingite-k?+

Mohs hardness is ~5. Luster: vitreous. The streak is white. Common colors include colorless, light yellow, orange, red.

Where is paulingite-k found?+

Notable localities include Rock Island Dam, on the Columbia River, Wenatchee, Douglas Co., Washington, USA; Riggins, Idaho Co., USA; Three Mile Creek, near Ritter, Grant Co., Oregon, USA; Chase Creek, at the junction with Charcoal Creek, north of Falkland, British Columbia, Canada; Giant's Causeway and Craigahulliar, Portrush, Co. Antrim, Ireland.

What rocks look like paulingite-k?+

Paulingite-K is most often confused with Analcime, Chabazite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with paulingite-k?+

Paulingite-K commonly co-occurs with Zeolites, Pyrite, Calcite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does paulingite-k form in?+

Where it forms: In vesicles in basalt flows. Working float back to the host body is the standard way to chase a fresh occurrence.

What is paulingite-k used for?+

Paulingite-K is used in collector.

Find paulingite-k on the map

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