Teepleite is a rare borate mineral typically found as small, colorless to yellowish tabular crystals within saline evaporite deposits. It is best identified by its occurrence in specific dry lake bed environments associated with other boron minerals like borax.
Is this teepleite?
5-step field checkRun through these checks against the specimen in your hand. The more boxes tick, the more confident the ID.
- 1Test the hardnessTry to scratch teepleite with a known reference. Teepleite sits at Mohs 3-3.5, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Streak: white.
- 3Read the lusterHold the specimen under a strong light. Luster: vitreous to greasy, dulled on exposure to air.
- 4Match the color rangeCompare against the expected color range: colorless, white.
- 5Look at form & habitCrystal system: tetragonal. Typical habit: tabular crystals, sometimes in crusts or granular aggregates.
Often confused with
Teepleite vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside teepleite
Minerals reported to co-occur with teepleite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Na₂B(OH)₄Cl
- Mohs hardness
- 3-3.5
- Density
- 2.076 g/cm³
- Streak
- White
- Luster
- Vitreous to greasy, dulled on exposure to air
- Transparency
- Transparent
- Crystal system
- Tetragonal
- Crystal habit
- Tabular crystals, sometimes in crusts or granular aggregates
- Cleavage
- Indistinct
- Rarity
- Rare
- Uses
- Collector
- Host rock
- Formed by reaction of boron-rich brines with halite in an extremely desiccated lake (Borax Lake, California, USA)
Where rockhounds find teepleite
Classic worldwide localities
- Borax Lake, Lake Co., and in Searles Lake, San Bernardino Co, California, USA
Field-hunting tip
Where it forms: Formed by reaction of boron-rich brines with halite in an extremely desiccated lake (Borax Lake, California, USA). If you start seeing halite, trona, burkeite in float, you are in the right ground. Typical habit: tabular crystals, sometimes in crusts or granular aggregates. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify teepleite?+
Where is teepleite found?+
What rocks look like teepleite?+
What minerals are found with teepleite?+
What kind of rock does teepleite form in?+
What is teepleite used for?+
Find teepleite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
