Goosecreekite is a relatively rare member of the zeolite group often forming small, clear, tabular crystals in volcanic cavities. It is best identified by its association with other zeolites and its distinctive monoclinic crystal habit in basaltic environments.

Hardness

~4.5

Mohs

Luster

Vitreous to pearly on crystal faces

Streak

White

Transparency

Transparent

mineralrareZeolite Group family

Goosecreekite

Hardness: ~4.5
Luster: Vitreous to pearly on crystal faces
Streak: White
Transparency: Transparent

Is this goosecreekite?

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 goosecreekite with a known reference. Goosecreekite sits at Mohs ~4.5, 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 to pearly on crystal faces.
4
Match the color range
Compare against the expected color range: colorless, white.
5
Look at form & habit
Crystal system: monoclinic. Typical habit: aggregates, euhedral crystals.

Often confused with

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

Often found alongside goosecreekite

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

All properties

Chemical formula: CaAl₂Si₆O₁₆·5H₂O
Mohs hardness: ~4.5
Density: 2.21 g/cm³
Colors: Colorless White
Streak: White
Luster: Vitreous to pearly on crystal faces
Transparency: Transparent
Crystal system: Monoclinic
Crystal habit: Aggregates, euhedral crystals
Cleavage: {010}, perfect
Rarity: Rare
Uses: Collector
Host rock: A late-stage mineral in vugs and fractures in a Triassic diabase (Goose Creek quarry, Virginia, USA); in cavities in basalt (Nasik, India)

Where rockhounds find goosecreekite

Classic worldwide localities

Goose Creek quarry, Leesburg, Loudoun Co., Virginia, USA
Pandulena quarry, Nasik, Maharashtra, India
Oberbaumühle quarry, Windischeschenbach, Bavaria, Germany

Field-hunting tip

Where it forms: A late-stage mineral in vugs and fractures in a Triassic diabase (Goose Creek quarry, Virginia, USA); in cavities in basalt (Nasik, India). If you start seeing prehnite, actinolite, chlorite in float, you are in the right ground. Typical habit: aggregates, euhedral crystals. Train your eye for that shape before scanning the outcrop.

Common questions

How do you identify goosecreekite?+

Mohs hardness is ~4.5. Luster: vitreous to pearly on crystal faces. The streak is white. Common colors include colorless, white.

Where is goosecreekite found?+

Notable localities include Goose Creek quarry, Leesburg, Loudoun Co., Virginia, USA; Pandulena quarry, Nasik, Maharashtra, India; Oberbaumühle quarry, Windischeschenbach, Bavaria, Germany.

What rocks look like goosecreekite?+

Goosecreekite is most often confused with Heulandite, Stilbite, Epistilbite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with goosecreekite?+

Goosecreekite commonly co-occurs with Prehnite, Actinolite, Chlorite, Epidote, Babingtonite, Quartz. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does goosecreekite form in?+

Where it forms: A late-stage mineral in vugs and fractures in a Triassic diabase (Goose Creek quarry, Virginia, USA); in cavities in basalt (Nasik, India). Working float back to the host body is the standard way to chase a fresh occurrence.

What is goosecreekite used for?+

Goosecreekite is used in collector.

Find goosecreekite on the map

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