Ammoniolasalite is a rare magnesium vanadate, typically bright orange to orange-yellow. It is a product of postmining oxidation of primary montroseite-corvusite assemblages at ambient temperatures. Associated minerals include ammoniozippeite, schindlerite and wernerbaurite. It was first described from Burro mine, Slick Rock district, San Miguel County, Colorado, USA.
Is this ammoniolasalite?
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 ammoniolasalite with a known reference. Ammoniolasalite sits at Mohs ~1, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Streak: light orange.
- 3Read the lusterHold the specimen under a strong light. Luster: vitreous.
- 4Match the color rangeCompare against the expected color range: bright orange, orange-yellow.
- 5Look at form & habitCrystal system: monoclinic.
Often confused with
Ammoniolasalite vs. its common look-alikes, and how to tell them apart in the field.
How to tell apart: Halite is the harder of the two (Mohs 2-2.5 vs. ~1); streak differs, so Ammoniolasalite leaves light orange, Halite leaves white.
How to tell apart: Sylvite is the harder of the two (Mohs 2 vs. ~1); streak differs, so Ammoniolasalite leaves light orange, Sylvite leaves white.
Often found alongside ammoniolasalite
Minerals reported to co-occur with ammoniolasalite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- [(NH₄)₂Mg₂(H₂O)₂₀]·[V₁₀O₂₈]
- Mohs hardness
- ~1
- Density
- 2.82 g/cm³
- Streak
- Light orange
- Luster
- Vitreous
- Transparency
- Transparent
- Crystal system
- Monoclinic
- Cleavage
- None
- Rarity
- Rare
- Uses
- Collector, Scientific research
- Host rock
- Product of postmining oxidation of primary montroseite-corvusite assemblages at ambient temperatures
Where rockhounds find ammoniolasalite
Classic worldwide localities
- Burro mine, Slick Rock district, San Miguel County, Colorado, USA
Field-hunting tip
Where it forms: Product of postmining oxidation of primary montroseite-corvusite assemblages at ambient temperatures. If you start seeing ammoniozippeite, schindlerite, wernerbaurite in float, you are in the right ground.
Common questions
How do you identify ammoniolasalite?+
Where is ammoniolasalite found?+
Is ammoniolasalite safe to handle?+
What rocks look like ammoniolasalite?+
What minerals are found with ammoniolasalite?+
What kind of rock does ammoniolasalite form in?+
What is ammoniolasalite used for?+
Find ammoniolasalite on the map
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