Ye'elimite is a rare calcium sulfoaluminate mineral typically found in the high-temperature combustion metamorphic rocks of the Hatrurim Formation. It is most notable for its primary role as a key constituent in calcium sulfoaluminate (CSA) cements, rather than its presence in hand specimens. Collectors typically search for it as small inclusions or crystalline grains within carbonate-rich rocks.

Hardness

5-6

Mohs

Luster

Vitreous

Streak

White

Transparency

Semitransparent

mineralrare

Ye'elimite

Hardness: 5-6
Luster: Vitreous
Streak: White
Transparency: Semitransparent

Is this ye'elimite?

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 ye'elimite with a known reference. Ye'elimite sits at Mohs 5-6, 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.
5
Look at form & habit
Crystal system: cubic. Typical habit: equant grains, massive.

Often confused with

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

Often found alongside ye'elimite

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

All properties

Chemical formula: Ca₄Al₆O₁₂SO₄
Mohs hardness: 5-6
Density: 2.61 g/cm³
Colors: Colorless
Streak: White
Luster: Vitreous
Transparency: Semitransparent
Crystal system: Cubic
Crystal habit: Equant grains, massive
Cleavage: None
Rarity: Rare
Uses: Industrial, Collector
Host rock: In a high-temperature (> 900°C) metamorphic assemblage in cobbles in a pseudo-conglomerate

Where rockhounds find ye'elimite

Classic worldwide localities

Hatrurim basin, W of the Dead Sea, Israel, near Har Ye'elim and Nahal Ye'elim (a hill and a wadi) (type locality)

Field-hunting tip

Where it forms: In a high-temperature (> 900°C) metamorphic assemblage in cobbles in a pseudo-conglomerate. If you start seeing larnite, brownmillerite, sulfatian-phosphatian fluorapatite in float, you are in the right ground. Typical habit: equant grains, massive. Train your eye for that shape before scanning the outcrop.

Common questions

How do you identify ye'elimite?+

Mohs hardness is 5-6. Luster: vitreous. The streak is white. Common colors include colorless.

Where is ye'elimite found?+

Notable localities include Hatrurim basin, W of the Dead Sea, Israel, near Har Ye'elim and Nahal Ye'elim (a hill and a wadi) (type locality).

What rocks look like ye'elimite?+

Ye'elimite is most often confused with Gehlenite, Anorthite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with ye'elimite?+

Ye'elimite commonly co-occurs with Larnite, Brownmillerite, Sulfatian-phosphatian fluorapatite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does ye'elimite form in?+

Where it forms: In a high-temperature (> 900°C) metamorphic assemblage in cobbles in a pseudo-conglomerate. Working float back to the host body is the standard way to chase a fresh occurrence.

What is ye'elimite used for?+

Ye'elimite is used in industrial, collector.

Find ye'elimite on the map

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