Lonecreekite is an extremely rare ammonium iron sulfate mineral that forms as small, colorless octahedrons. It is typically found as a secondary mineral in shale, resulting from the weathering of iron-rich sulfides, and is highly soluble in water, requiring dry storage for preservation.

Hardness

Mohs

Luster

Vitreous

Streak

White

Transparency

Transparent

mineralrareAlums Group family

Lonecreekite

Hardness: 2
Luster: Vitreous
Streak: White
Transparency: Transparent

Is this lonecreekite?

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 lonecreekite with a known reference. Lonecreekite sits at Mohs 2 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Lonecreekite leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Lonecreekite typically shows a vitreous luster.
4
Match the color range
Compare against the expected color range: colorless, white.
5
Look at form & habit
Crystal system: cubic. Typical habit: octahedral crystals.

Often confused with

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

Often found alongside lonecreekite

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

Tschermigite
mineral · Mohs 1.5-2

All properties

Chemical formula: (NH₄)Fe(SO₄)₂·12H₂O
Mohs hardness: 2
Density: 1.82 g/cm³
Colors: Colorless White
Streak: White
Luster: Vitreous
Transparency: Transparent
Crystal system: Cubic
Crystal habit: Octahedral Crystals
Cleavage: None
Rarity: Rare
Uses: Collector
Host rock: Shale
Typical price: $50-300 per specimen

Where rockhounds find lonecreekite

Classic worldwide localities

Lone Creek Falls, Mpumalanga, South Africa

Field-hunting tip

Look in shale country — that is the host setting where lonecreekite typically forms. If you start seeing tschermigite in float, you are in the right ground. Field specimens usually show a octahedral crystals habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify lonecreekite?+

Mohs hardness is 2. It typically shows a vitreous luster. The streak is white. Common colors include colorless, white.

Where is lonecreekite found?+

Notable localities include Lone Creek Falls, Mpumalanga, South Africa.

How much is lonecreekite worth?+

Typical asking prices fall in the range of $50-300 per specimen. Quality, size, and provenance can move individual specimens well outside that range.

What rocks look like lonecreekite?+

Lonecreekite is most often confused with Tschermigite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with lonecreekite?+

Lonecreekite commonly co-occurs with Tschermigite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does lonecreekite form in?+

Lonecreekite typically forms in shale. Working float back to the host body is the standard way to chase a fresh occurrence.

What is lonecreekite used for?+

Lonecreekite is used in collector.

Find lonecreekite on the map

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