PHARMACOALUMITE Mineral Details

Complete mineralogical data for PHARMACOALUMITE. Chemical Formula: KAl4(AsO4)3(OH)4·6.5H2O. Crystal System: Isometric. Learn about its geologic occurrence, habit, and identification.

PHARMACOALUMITE

KAl4(AsO4)3(OH)4·6.5H2O

Crystal System

Isometric

Crystal Class

Cubic hextetrahedral

Space Group

P43m

Point Group

4 3 m

Structure & Data

Crystal Structure

Phosphates, arsenates, vanadates: anions [PO4]3-, [AsO4]3-, [VO4]3- are usually insular; cations may be small with [4] coordination, medium-sized with [6] coordination, or large with [8] or higher coordination; medium-sized cations with octahedral [6] coordination may be insular, corner-, edge- or face-sharing & form major structural units with add’l anions with H2O with large & medium-sized cations, (OH, etc.):RO4 > 1:1 & < 2:1; clusters of 4 edge-sharing Al[6] octahedra linked by 6 AsO4 tetrahedra to form framework with large cavities contain H2O molecules & large cations.2 Renamed from aluminopharmacosiderite & structure confirmed.3

Cell Data

a=7.75Å, Z=1

Geology & Identification

Geologic Occurrence

Alteration product of arsenopyritePHARMACOALUMITEPHARMACOALUMITE

Habit

Cubic crystals, in aggregates

Twinning

Relationships

RELATIONSHIP TO OTHER MINERALS

Pharmacosiderite supergroup, pharmacoalumite group; Al analog of pharmacosiderite

If you are fascinated by the hidden structures of our planet, you have likely come across PHARMACOALUMITE. This mineral is a compelling subject for study, offering a unique glimpse into the complex chemistry that shapes the Earth’s crust.Whether you are a student identifying a hand sample, a researcher looking for crystallographic data, or a collector curious about a new find, this guide breaks down everything you need to know about PHARMACOALUMITE. From its precise chemical formula to the geological environments where it thrives, let’s explore what makes this mineral distinct.

The Chemistry Behind the Crystal

Every mineral tells a story through its chemistry. At its core, PHARMACOALUMITE is defined by the chemical formula KAl4(AsO4)3(OH)4·6.5H2O.This isn’t just a string of letters and numbers; it represents the precise recipe of elements that nature used to build this specimen. This specific chemical composition is what gives the mineral its stability and dictates how it reacts with acids, heat, or other minerals. It is the fundamental “DNA” that geologists use to classify it within the larger mineral kingdom.

Crystallography: Geometry in Nature

One of the most beautiful aspects of mineralogy is the hidden geometry within every stone. PHARMACOALUMITE crystallizes in the Isometric system.Think of this as the mineral’s architectural blueprint. It dictates the symmetry and the angles at which the crystal faces grow. Digging deeper into its symmetry, it falls under the Cubic hextetrahedral.
  • Point Group: 4 3 m
  • Space Group: P43m
READ ALSO  CHESTERMANITE Mineral Details
Why does this matter? These crystallographic details are like a fingerprint. They influence optical properties—how light travels through the crystal—and physical traits like how it breaks or cleaves when struck.

Internal Structure and Unit Cell

If we could zoom in to the atomic level, we would see the “Unit Cell”—the smallest repeating box of atoms that builds up the entire crystal. For PHARMACOALUMITE, the dimensions of this microscopic building block are:
a=7.75Å, Z=1
The internal arrangement of these atoms is described as:Phosphates, arsenates, vanadates: anions [PO4]3-, [AsO4]3-, [VO4]3- are usually insular; cations may be small with [4] coordination, medium-sized with [6] coordination, or large with [8] or higher coordination; medium-sized cations with octahedral [6] coordination may be insular, corner-, edge- or face-sharing & form major structural units with add’l anions with H2O with large & medium-sized cations, (OH, etc.):RO4 > 1:1 & < 2:1; clusters of 4 edge-sharing Al[6] octahedra linked by 6 AsO4 tetrahedra to form framework with large cavities contain H2O molecules & large cations.2 Renamed from aluminopharmacosiderite & structure confirmed.3This internal structure is the invisible framework that supports everything we see on the outside, from the mineral’s density to its hardness.

Physical Appearance (Habit)

When you find PHARMACOALUMITE in the field, what does it actually look like? A mineral’s “habit” describes its typical shape and growth pattern.
  • Common Habit: Cubic crystals, in aggregates
  • Twinning: 
READ ALSO  FERROWYLLIEITE Mineral Details
Twinning is a fascinating phenomenon where two or more crystals grow interlocked in a specific symmetrical pattern. If PHARMACOALUMITE exhibits twinning, it can be a dead giveaway for identification, distinguishing it from look-alike minerals.

Where is it Found? (Geologic Occurrence)

Minerals are the products of their environment. They don’t just appear anywhere; they need specific conditions—pressure, temperature, and chemical ingredients—to form.Geologic Occurrence: Alteration product of arsenopyriteKnowing this context helps geologists reconstruct the history of a rock formation. It tells us whether the rock was born from cooling magma, settled in an ancient ocean, or was transformed by the intense heat and pressure of metamorphism. For more broad geological context, resources like the U.S. Geological Survey (USGS) provide excellent maps and data.

Related Minerals

No mineral exists in a vacuum. PHARMACOALUMITE is often related to other species, either through similar chemistry or structure.Relationship Data: Pharmacosiderite supergroup, pharmacoalumite group; Al analog of pharmacosideriteUnderstanding these relationships is key. It helps us see the “family tree” of the mineral world, showing how different elements can substitute for one another to create an entirely new species with similar properties.

Frequently Asked Questions (FAQs)

1. What is the chemical formula of PHARMACOALUMITE?The standard chemical formula for PHARMACOALUMITE is KAl4(AsO4)3(OH)4·6.5H2O. This defines its elemental composition.2. Which crystal system does PHARMACOALUMITE belong to?PHARMACOALUMITE crystallizes in the Isometric system. Its internal symmetry is further classified under the Cubic hextetrahedral class.
READ ALSO  AKAGANEITE Mineral Details
3. How is PHARMACOALUMITE typically found in nature?The “habit” or typical appearance of PHARMACOALUMITE is described as Cubic crystals, in aggregates. This refers to the shape the crystals take when they grow without obstruction.4. In what geological environments does PHARMACOALUMITE form?PHARMACOALUMITE is typically found in environments described as: Alteration product of arsenopyrite. This gives clues to the geological history of the area where it is discovered.5. Are there other minerals related to PHARMACOALUMITE?Yes, it is often associated with or related to other minerals such as: Pharmacosiderite supergroup, pharmacoalumite group; Al analog of pharmacosiderite.

External Resources for Further Study

For those looking to dive deeper into the specific mineralogical data of PHARMACOALUMITE, we recommend checking high-authority databases:

Final Thoughts

PHARMACOALUMITE is more than just a name on a list; it is a testament to the orderly and beautiful laws of nature. With a chemical backbone of KAl4(AsO4)3(OH)4·6.5H2O and a structure defined by the Isometric system, it holds a specific and important place in the study of mineralogy.We hope this overview has helped clarify the essential data points for this specimen. Whether for academic study or personal interest, understanding these properties brings us one step closer to understanding the Earth itself.
Scroll to Top