Eakerite is an exceptionally rare calcium-tin silicate mineral typically found as small, clear, tabular crystals. It is primarily known from the Livingston Mine in North Carolina, where it occurs within skarn environments alongside various silicates. Due to its extreme rarity and very limited occurrence, it is highly sought after by advanced mineral collectors.

Hardness

5.5

Mohs

Luster

Vitreous

Streak

White

Transparency

Transparent to translucent

mineralrare

Eakerite

Hardness: 5.5
Luster: Vitreous
Streak: White
Transparency: Transparent to translucent

Is this eakerite?

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 eakerite with a known reference. Eakerite sits at Mohs 5.5, 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, white.
5
Look at form & habit
Crystal system: monoclinic. Typical habit: tabular crystals.

Often confused with

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

Often found alongside eakerite

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

All properties

Chemical formula: Ca₂SnAl₂Si₆O₁₈(OH)₂·2H₂O
Mohs hardness: 5.5
Density: 2.93 g/cm³
Colors: Colorless White
Streak: White
Luster: Vitreous
Transparency: Transparent to translucent
Crystal system: Monoclinic
Crystal habit: Tabular crystals
Cleavage: None
Rarity: Rare
Uses: Collector
Host rock: Probably of hydrothermal origin, in a seam in spodumene-bearing pegmatite (Foote mine, North Carolina, USA); as exsolved inclusions in stanniferous andradite (Kitel'skoye deposit, Karelia)

Where rockhounds find eakerite

Classic worldwide localities

Foote mine, Kings Mountain, Cleveland Co., North Carolina, USA
Kitel'skoye tin skarn deposit, north of Lake Lagoda, Karelia

Field-hunting tip

Where it forms: Probably of hydrothermal origin, in a seam in spodumene-bearing pegmatite (Foote mine, North Carolina, USA); as exsolved inclusions in stanniferous andradite (Kitel'skoye deposit, Karelia). If you start seeing tetrawickmanite, bavenite, quartz in float, you are in the right ground. Typical habit: tabular crystals. Train your eye for that shape before scanning the outcrop.

Common questions

How do you identify eakerite?+

Mohs hardness is 5.5. Luster: vitreous. The streak is white. Common colors include colorless, white.

Where is eakerite found?+

Notable localities include Foote mine, Kings Mountain, Cleveland Co., North Carolina, USA; Kitel'skoye tin skarn deposit, north of Lake Lagoda, Karelia.

What rocks look like eakerite?+

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

What minerals are found with eakerite?+

Eakerite commonly co-occurs with Tetrawickmanite, Bavenite, Quartz, Albite, Andradite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does eakerite form in?+

Where it forms: Probably of hydrothermal origin, in a seam in spodumene-bearing pegmatite (Foote mine, North Carolina, USA); as exsolved inclusions in stanniferous andradite (Kitel'skoye deposit, Karelia). Working float back to the host body is the standard way to chase a fresh occurrence.

What is eakerite used for?+

Eakerite is used in collector.

Find eakerite on the map

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