Blödite is a sulfate mineral that forms in saline evaporite deposits, often found as well-developed, glassy, prismatic crystals. It is highly water-soluble, so it should be kept in a dry environment and protected from humidity to prevent degradation. It is most commonly found in association with other evaporite minerals in salt mines and saline lake environments.
Is this blödite?
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 blödite with a known reference. Blödite sits at Mohs 2.5-3, 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.
- 4Match the color rangeCompare against the expected color range: colorless, green, yellow, red.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: compact, massive.
Often confused with
Blödite vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside blödite
Minerals reported to co-occur with blödite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Na₂Mg(SO₄)₂·4H₂O
- Mohs hardness
- 2.5-3
- Density
- 2.218-2.24 g/cm³
- Streak
- White
- Luster
- Vitreous
- Transparency
- Transparent to translucent
- Crystal system
- Monoclinic
- Crystal habit
- Compact, massive
- Cleavage
- Poor on {111}
- Rarity
- Common
- Uses
- Collector
- Host rock
- In lacustrine salt deposits and salt efflorescences; probably a product of metamorphism of marine salt deposits; in nitrate deposits; may be a volcanic sublimate
Where rockhounds find blödite
Classic worldwide localities
- Green River Formation, Garfield and Rio Blanco Cos., Colorado, USA
- Great Salt Lake, Davis Co., Utah, USA
- Soda Lake, Carrizo Plain, San Luis Obispo Co., and at Bertram Siding, Salton Sea, Imperial Co., California, USA
- Laguna Salina, Estancia Valley, Torrance Co., New Mexico, USA
- Ischl and Hallstatt, Austria
- Stassfurt district, Saxony-Anhalt, Germany
Field-hunting tip
Where it forms: In lacustrine salt deposits and salt efflorescences; probably a product of metamorphism of marine salt deposits; in nitrate deposits; may be a volcanic sublimate. If you start seeing halite, kainite, carnallite in float, you are in the right ground. Typical habit: compact, massive. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify blödite?+
Where is blödite found?+
What rocks look like blödite?+
What minerals are found with blödite?+
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Find blödite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
