If you are fascinated by the hidden structures of our planet, you have likely come across
BURNSITE. 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
BURNSITE. 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,
BURNSITE is defined by the chemical formula
KCdCu7(Se4+O3)2O2Cl9.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.
BURNSITE crystallizes in the
Hexagonal 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
Dihexagonal dipyramidal.
- Point Group: 6/m 2/m 2/m
- Space Group: P63/mmc
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
BURNSITE, the dimensions of this microscopic building block are:
a=8.78Å, c=15.52Å, Z=2
The internal arrangement of these atoms is described as:
There are 2 non-equivalent Cu2+ cations in 2 structure; 2 Cu(1) cation is coordinated by 3 O atoms & 3 of Cl; this is 1st of this type of mixed-ligand Cu2+Φ6 (Φ:O2-, Cl-) octahedron; octahedron is (2+4)-distorted owing to Jahn-Teller effect in contrast to vast majority of Cu2+ oxysalt minerals that contain (4+2)- distorted Cu2+ octahedra; Cu(2) cation is coordinated by 2 O & 3 Cl anions arranged at vertices of trig bi-∆; this is 1st occur-rence of mixed-ligand Cu2+O2Cl3 trig bi-∆ in mineral; single symmetrically independent Cd2+ cation is coordinated by 6 Cl anions loc at vertices of regular octahedron; structure contains 1 symmetrically independent K cation that is coordinated by 6 Cl anions in trig prismatic array; there is unique Se4+ cation that is strongly bonded to 3 O anions on 1 side of cation, owing to presence of s2 lone-electron pair; structure is described both in terms of cation-centered polyhedra & oxocentered OCu4 tetrahedra; structure of burnsite is closely related to structures of other natural Cu oxide chloride selenites discovered in Tolbachik fumaroles (chloromenite, georgbokiite, ilinskite).This 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
BURNSITE in the field, what does it actually look like? A mineral’s “habit” describes its typical shape and growth pattern.
- Common Habit: As anhedral equidimensional micro grains
- Twinning:
Twinning is a fascinating phenomenon where two or more crystals grow interlocked in a specific symmetrical pattern. If BURNSITE 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:
Fumarolic sublimateKnowing 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.
BURNSITE is often related to other species, either through similar chemistry or structure.
Relationship Data:
Chemically related georgbokiite, chloromenite, ilinskiteUnderstanding 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 BURNSITE?The standard chemical formula for BURNSITE is
KCdCu7(Se4+O3)2O2Cl9. This defines its elemental composition.
2. Which crystal system does BURNSITE belong to?BURNSITE crystallizes in the
Hexagonal system. Its internal symmetry is further classified under the Dihexagonal dipyramidal class.
3. How is BURNSITE typically found in nature?The “habit” or typical appearance of BURNSITE is described as
As anhedral equidimensional micro grains. This refers to the shape the crystals take when they grow without obstruction.
4. In what geological environments does BURNSITE form?BURNSITE is typically found in environments described as:
Fumarolic sublimate. This gives clues to the geological history of the area where it is discovered.
5. Are there other minerals related to BURNSITE?Yes, it is often associated with or related to other minerals such as:
Chemically related georgbokiite, chloromenite, ilinskite.
External Resources for Further Study
For those looking to dive deeper into the specific mineralogical data of
BURNSITE, we recommend checking high-authority databases:
Final Thoughts
BURNSITE 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
KCdCu7(Se4+O3)2O2Cl9 and a structure defined by the
Hexagonal 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.
