crystal class: meaning, definition, pronunciation and examples
Very Low (Academic/Specialist)Highly Technical / Scientific
Quick answer
What does “crystal class” mean?
In crystallography, one of the 32 possible categories of symmetrical forms that crystals can take, based on their point group symmetry. It describes the set of symmetry operations that leave the crystal's external shape unchanged.
Audio
Pronunciation
Definition
Meaning and Definition
In crystallography, one of the 32 possible categories of symmetrical forms that crystals can take, based on their point group symmetry. It describes the set of symmetry operations that leave the crystal's external shape unchanged.
Can occasionally be used metaphorically in specialized fields (e.g., materials science, mathematics) to refer to a fundamental category or classification system with rigid, defined properties.
Dialectal Variation
British vs American Usage
Differences
No significant differences in meaning or usage. Spelling conventions follow national norms for other terms in the same sentence.
Connotations
Identical technical connotations in both varieties.
Frequency
Identically rare, confined to geology, mineralogy, chemistry, and materials science texts.
Grammar
How to Use “crystal class” in a Sentence
The mineral belongs to the [crystal class] of cubic hexoctahedral.Researchers determined its [crystal class] using X-ray diffraction.A crystal's class is defined by its [symmetry elements].Vocabulary
Collocations
Usage
Meaning in Context
Business
Virtually never used.
Academic
Primary context. Used in geology, chemistry, materials science, and physics papers and textbooks to precisely describe mineral and synthetic crystal structures.
Everyday
Never used.
Technical
Core term in crystallography, mineralogy, solid-state physics, and materials engineering for classification and analysis.
Vocabulary
Synonyms of “crystal class”
Neutral
Weak
Vocabulary
Antonyms of “crystal class”
Watch out
Common Mistakes When Using “crystal class”
- Using 'crystal class' interchangeably with 'crystal system'. (A system contains several classes.)
- Pronouncing 'class' with a long /a:/ in American English (should be /æ/).
- Treating it as an uncountable or mass noun.
FAQ
Frequently Asked Questions
No. Crystal system (e.g., cubic, hexagonal) is a broader category. There are 7 systems, which are subdivided into the 32 crystal classes based on more detailed symmetry.
It is essential in crystallography, mineralogy, solid-state physics, materials science, and inorganic chemistry for the precise description and identification of crystalline materials.
Extremely unlikely outside of specialized academic textbooks, research papers, or advanced courses in the earth sciences or materials engineering.
Mathematical derivation from the possible combinations of symmetry elements (rotation axes, mirror planes, inversion center) that are compatible with the translation-free (point) symmetry of three-dimensional periodic structures.
In crystallography, one of the 32 possible categories of symmetrical forms that crystals can take, based on their point group symmetry. It describes the set of symmetry operations that leave the crystal's external shape unchanged.
Crystal class is usually highly technical / scientific in register.
Crystal class: in British English it is pronounced /ˌkrɪs.təl ˈklɑːs/, and in American English it is pronounced /ˌkrɪs.təl ˈklæs/. Tap the audio buttons above to hear it.
Learning
Memory Aids
Mnemonic
Imagine 32 different 'classes' in a school, each with a unique, rigid set of rules (symmetry operations) that the students (crystal faces) must follow to shape their class (crystal form).
Conceptual Metaphor
CLASSROOM / TAXONOMY: A crystal class is like a specific classroom with a strict rulebook (symmetry) that dictates how the desks (atoms) can be arranged.
Practice
Quiz
What does 'crystal class' specifically describe?