Nitromagnesite is a highly soluble nitrate mineral that typically forms as efflorescent crusts in arid environments. It is extremely sensitive to humidity and will readily deliquesce or dehydrate, requiring specialized climate-controlled storage for preservation.

Hardness
1.5-2
Mohs
Luster
Vitreous
Streak
White
Transparency
Transparent

Is this nitromagnesite?

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 nitromagnesite with a known reference. Nitromagnesite sits at Mohs 1.5-2 — softer than the next harder reference, harder than the previous one.
  • 2
    Check the streak
    Drag the specimen across an unglazed porcelain plate. Nitromagnesite leaves a white streak.
  • 3
    Read the luster
    Hold the specimen under a strong light. Nitromagnesite typically shows a vitreous luster.
  • 4
    Match the color range
    Compare against the expected color range: white, colorless.
  • 5
    Look at form & habit
    Crystal system: monoclinic. Typical habit: efflorescent crusts, acicular needles, fibrous masses.

Often confused with

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

Often found alongside nitromagnesite

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

All properties

Chemical formula
Mg(NO₃)₂·6H₂O
Mohs hardness
1.5-2
Density
1.63 g/cm³
Streak
White
Luster
Vitreous
Transparency
Transparent
Crystal system
Monoclinic
Crystal habit
Efflorescent Crusts, Acicular Needles, Fibrous Masses
Cleavage
Perfect
Rarity
Rare
Uses
Collector
Host rock
Arid Caves, Caliche Deposits, Dry Nitrate-rich Soils
Typical price
$20-100 for small study specimens

Where rockhounds find nitromagnesite

Classic worldwide localities

  • Chile
  • Spain
  • Italy
  • USA

Field-hunting tip

Look in arid caves, caliche deposits, dry nitrate-rich soils country — that is the host setting where nitromagnesite typically forms. If you start seeing nitronatrite, gypsum, halite in float, you are in the right ground. Field specimens usually show a efflorescent crusts, acicular needles, fibrous masses habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify nitromagnesite?+
Mohs hardness is 1.5-2. It typically shows a vitreous luster. The streak is white. Common colors include white, colorless.
Where is nitromagnesite found?+
Notable localities include Chile; Spain; Italy; USA.
How much is nitromagnesite worth?+
Typical asking prices fall in the range of $20-100 for small study specimens. Quality, size, and provenance can move individual specimens well outside that range.
What rocks look like nitromagnesite?+
Nitromagnesite is most often confused with Nitrocalcite. A quick hardness test and a streak check separate the look-alikes faster than color alone.
What minerals are found with nitromagnesite?+
Nitromagnesite commonly co-occurs with Nitronatrite, Gypsum, Halite. Spotting any of these in float or country rock is a useful trip signal.
What kind of rock does nitromagnesite form in?+
Nitromagnesite typically forms in arid caves, caliche deposits, dry nitrate-rich soils. Working float back to the host body is the standard way to chase a fresh occurrence.
What is nitromagnesite used for?+
Nitromagnesite is used in collector.

Find nitromagnesite on the map

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