Burkeite is a rare carbonate-sulfate mineral typically found in the evaporite deposits of ancient or active alkaline salt lakes. Collectors prize it for its unique, often slightly rounded dipyramidal crystal forms, which are most famously associated with the brine deposits of Searles Lake in California.

Hardness

3.5

Mohs

Luster

Vitreous

Streak

White

Transparency

Translucent

mineralrare

Burkeite

Hardness: 3.5
Luster: Vitreous
Streak: White
Transparency: Translucent

Is this burkeite?

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 burkeite with a known reference. Burkeite sits at Mohs 3.5 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Burkeite leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Burkeite typically shows a vitreous luster.
4
Match the color range
Compare against the expected color range: white, gray, pale yellow.
5
Look at form & habit
Crystal system: orthorhombic. Typical habit: pyramidal to dipyramidal crystals, often rounded or massive.

Often confused with

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

Often found alongside burkeite

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

All properties

Chemical formula: Na₆(CO₃)(SO₄)₂
Mohs hardness: 3.5
Density: 2.57 g/cm³
Colors: White Gray Pale Yellow
Streak: White
Luster: Vitreous
Transparency: Translucent
Crystal system: Orthorhombic
Crystal habit: Pyramidal to Dipyramidal Crystals, Often Rounded or Massive
Cleavage: None
Rarity: Rare
Uses: Collector, Research
Host rock: Evaporite Deposits in Alkaline Salt Lakes
Typical price: $20-100 per specimen

Where rockhounds find burkeite

Classic worldwide localities

Searles Lake, California, USA
Borax Lake, California, USA
Lake Natron, Tanzania

Field-hunting tip

Look in evaporite deposits in alkaline salt lakes country — that is the host setting where burkeite typically forms. If you start seeing trona, thenardite, borax in float, you are in the right ground. Field specimens usually show a pyramidal to dipyramidal crystals, often rounded or massive habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify burkeite?+

Mohs hardness is 3.5. It typically shows a vitreous luster. The streak is white. Common colors include white, gray, pale yellow.

Where is burkeite found?+

Notable localities include Searles Lake, California, USA; Borax Lake, California, USA; Lake Natron, Tanzania.

How much is burkeite worth?+

Typical asking prices fall in the range of $20-100 per specimen. Quality, size, and provenance can move individual specimens well outside that range.

What rocks look like burkeite?+

Burkeite is most often confused with Trona, Thenardite, Gaylussite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with burkeite?+

Burkeite commonly co-occurs with Trona, Thenardite, Borax, Halite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does burkeite form in?+

Burkeite typically forms in evaporite deposits in alkaline salt lakes. Working float back to the host body is the standard way to chase a fresh occurrence.

What is burkeite used for?+

Burkeite is used in collector, research.

Find burkeite on the map

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