Para-alumohydrocalcite is a rare carbonate mineral found in hydrothermal environments and specific sedimentary formations. It typically occurs as delicate radial aggregates or crusts associated with other carbonate species. Due to its scarcity and similarity to other white hydrous carbonates, it is primarily a target for specialized mineral collectors.
Is this para-alumohydrocalcite?
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 para-alumohydrocalcite with a known reference. Para-alumohydrocalcite sits at Mohs 1.75, 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: white, colorless.
- 5Look at form & habitCrystal system: triclinic. Typical habit: aggregates, fibrous, radial.
Often confused with
Para-alumohydrocalcite vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside para-alumohydrocalcite
Minerals reported to co-occur with para-alumohydrocalcite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- CaAl₂(CO₃)₂(OH)₄·6H₂O
- Mohs hardness
- 1.75
- Density
- 2.0 g/cm³
- Streak
- White
- Luster
- Vitreous
- Transparency
- Semitransparent
- Crystal system
- Triclinic
- Crystal habit
- Aggregates, fibrous, radial
- Cleavage
- Perfect
- Rarity
- Rare
- Uses
- Collector
- Host rock
- In the oxidized zone of sulfur deposits, formed by decomposition of allophane (Vodin deposit, Russia; Gaurdak deposit, Turkmenistan)
Where rockhounds find para-alumohydrocalcite
Classic worldwide localities
- Vodin sulfur deposit, Samara district, Russia
- Gaurdak sulfur deposit, Turkmenistan
- Hampstead Farm quarry, Chipping Sodbury, Avon, and from Boughton, near Northampton, England
Field-hunting tip
Where it forms: In the oxidized zone of sulfur deposits, formed by decomposition of allophane (Vodin deposit, Russia; Gaurdak deposit, Turkmenistan). If you start seeing gypsum, calcite, halloysite in float, you are in the right ground. Typical habit: aggregates, fibrous, radial. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify para-alumohydrocalcite?+
Where is para-alumohydrocalcite found?+
What rocks look like para-alumohydrocalcite?+
What minerals are found with para-alumohydrocalcite?+
What kind of rock does para-alumohydrocalcite form in?+
What is para-alumohydrocalcite used for?+
Find para-alumohydrocalcite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
