Ericaite is a rare member of the boracite group typically found in marine evaporite sequences. It is most easily identified by its distinctive red to violet coloration and occurrence within salt beds alongside halite and sylvite.

Hardness

7-7.5

Mohs

Luster

Vitreous

Streak

White

Transparency

Semitransparent

mineralrareBoracite Group family

Ericaite

Hardness: 7-7.5
Luster: Vitreous
Streak: White
Transparency: Semitransparent

Is this ericaite?

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 ericaite with a known reference. Ericaite sits at Mohs 7-7.5, 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: red, purple, light green, black, brown.
5
Look at form & habit
Crystal system: orthorhombic. Typical habit: euhedral crystals, pseudo cubic.

Often confused with

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

Often found alongside ericaite

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

All properties

Chemical formula: Fe₃B₇O₁₃Cl
Mohs hardness: 7-7.5
Density: 3.17-3.22 g/cm³
Colors: Red Purple Light green Black Brown
Streak: White
Luster: Vitreous
Transparency: Semitransparent
Crystal system: Orthorhombic
Crystal habit: Euhedral crystals, pseudo cubic
Cleavage: None
Rarity: Rare
Uses: Collector
Host rock: An uncommon constituent of marine evaporite deposits

Where rockhounds find ericaite

Classic worldwide localities

Louann Salt Formation, Clarke Co., Alabama, USA
Wathlingen-Hänigsen, Lower Saxony, Germany
Bischofferode and Sondershausen, Thuringia, Germany
Boulby potash mine, northwest of Whitby, Yorkshire, England
Alto Chapare, Cochabamba, Bolivia

Field-hunting tip

Where it forms: An uncommon constituent of marine evaporite deposits. If you start seeing halite, sylvite, anhydrite in float, you are in the right ground. Typical habit: euhedral crystals, pseudo cubic. Train your eye for that shape before scanning the outcrop.

Common questions

How do you identify ericaite?+

Mohs hardness is 7-7.5. Luster: vitreous. The streak is white. Common colors include red, purple, light green, black.

Where is ericaite found?+

Notable localities include Louann Salt Formation, Clarke Co., Alabama, USA; Wathlingen-Hänigsen, Lower Saxony, Germany; Bischofferode and Sondershausen, Thuringia, Germany; Boulby potash mine, northwest of Whitby, Yorkshire, England; Alto Chapare, Cochabamba, Bolivia.

What rocks look like ericaite?+

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

What minerals are found with ericaite?+

Ericaite commonly co-occurs with Halite, Sylvite, Anhydrite, Kieserite, Danburite, Boracite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does ericaite form in?+

Where it forms: An uncommon constituent of marine evaporite deposits. Working float back to the host body is the standard way to chase a fresh occurrence.

What is ericaite used for?+

Ericaite is used in collector.

Find ericaite on the map

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