Podcast
Questions and Answers
What defines an atom in the context of matter?
What defines an atom in the context of matter?
Which term describes a smooth, flat break in a crystal?
Which term describes a smooth, flat break in a crystal?
What is the definition of a crystalline material?
What is the definition of a crystalline material?
What does 'doubly refractive' mean in terms of crystal properties?
What does 'doubly refractive' mean in terms of crystal properties?
Signup and view all the answers
Which term refers to visible shadow-like lines seen in a crystal?
Which term refers to visible shadow-like lines seen in a crystal?
Signup and view all the answers
In crystallography, what is meant by a glide plane?
In crystallography, what is meant by a glide plane?
Signup and view all the answers
What does 'specific gravity' measure in a material?
What does 'specific gravity' measure in a material?
Signup and view all the answers
What refers to the characteristic crystal shape or form of a mineral?
What refers to the characteristic crystal shape or form of a mineral?
Signup and view all the answers
What is defined as the force required to produce distortion in a crystal lattice?
What is defined as the force required to produce distortion in a crystal lattice?
Signup and view all the answers
Which type of diamond contains no easily measurable nitrogen or boron impurities?
Which type of diamond contains no easily measurable nitrogen or boron impurities?
Signup and view all the answers
What is a point defect that occurs when an atom is missing from its original position in the crystal lattice?
What is a point defect that occurs when an atom is missing from its original position in the crystal lattice?
Signup and view all the answers
Which of the following describes a triangular depression or protrusion occurring on a diamond's octahedral faces?
Which of the following describes a triangular depression or protrusion occurring on a diamond's octahedral faces?
Signup and view all the answers
What is the smallest group of atoms with the distinctive chemical composition and crystal structure of a mineral called?
What is the smallest group of atoms with the distinctive chemical composition and crystal structure of a mineral called?
Signup and view all the answers
Which type of diamond contains boron replacing carbon atoms in its crystal lattice?
Which type of diamond contains boron replacing carbon atoms in its crystal lattice?
Signup and view all the answers
What concept explains that the more dislocations present in a crystal, the more strain it experiences?
What concept explains that the more dislocations present in a crystal, the more strain it experiences?
Signup and view all the answers
What type of defect is indicated by mineral inclusions and voids in a diamond?
What type of defect is indicated by mineral inclusions and voids in a diamond?
Signup and view all the answers
What describes the characteristic geometric shape of a crystal?
What describes the characteristic geometric shape of a crystal?
Signup and view all the answers
Which of the following describes the regular, repeating arrangement of atoms in a mineral?
Which of the following describes the regular, repeating arrangement of atoms in a mineral?
Signup and view all the answers
What term refers to an imperfection or deviation in a crystal lattice regarding a point?
What term refers to an imperfection or deviation in a crystal lattice regarding a point?
Signup and view all the answers
Which type of bond is formed by two atoms sharing electrons?
Which type of bond is formed by two atoms sharing electrons?
Signup and view all the answers
Which of the following best describes the process in which a diamond's outer surface is partially dissolved?
Which of the following best describes the process in which a diamond's outer surface is partially dissolved?
Signup and view all the answers
What term is used for a solid mass of individual crystals held together by a natural binding agent?
What term is used for a solid mass of individual crystals held together by a natural binding agent?
Signup and view all the answers
What defines a set of parallel and evenly spaced planes distributed along certain crystal directions in which atoms are more closely packed?
What defines a set of parallel and evenly spaced planes distributed along certain crystal directions in which atoms are more closely packed?
Signup and view all the answers
Which term is used to describe minerals that possess different physical and optical properties in different directions?
Which term is used to describe minerals that possess different physical and optical properties in different directions?
Signup and view all the answers
What structural form is considered the most common habit of a gem diamond?
What structural form is considered the most common habit of a gem diamond?
Signup and view all the answers
Which type of diamond has nitrogen atoms replacing carbon atoms in its crystal lattice?
Which type of diamond has nitrogen atoms replacing carbon atoms in its crystal lattice?
Signup and view all the answers
Which of the following describes the point defect created when an atom is missing from its original position in the crystal lattice?
Which of the following describes the point defect created when an atom is missing from its original position in the crystal lattice?
Signup and view all the answers
What term refers to the three-dimensional imperfection or deviation in the arrangement of atoms in a crystal lattice ?
What term refers to the three-dimensional imperfection or deviation in the arrangement of atoms in a crystal lattice ?
Signup and view all the answers
Which category of defects in diamonds does not include mineral inclusions and voids?
Which category of defects in diamonds does not include mineral inclusions and voids?
Signup and view all the answers
What is the most precise method for determining the type of diamond?
What is the most precise method for determining the type of diamond?
Signup and view all the answers
What formation in diamonds consists of two or more parts that share crystal planes in a symmetrical manner?
What formation in diamonds consists of two or more parts that share crystal planes in a symmetrical manner?
Signup and view all the answers
What always mimics the habit of the host in crystallography?
What always mimics the habit of the host in crystallography?
Signup and view all the answers
Study Notes
Key Crystal Properties
- Aggregate: A solid mass of individual crystals intergrown or held together.
- Atom: The basic unit of matter.
- Cleavage: A smooth, flat break along a crystal plane.
- Cleavage Plane: A planar surface where a mineral tends to break due to atomic weakness.
- Crystal: Solid matter with repeating atom arrangements.
- Crystal Axes: A reference system to describe crystal symmetry and shape.
- Crystal Planes: Parallel and evenly spaced planes within a crystal structure, packed closely with atoms.
- Crystal Shape (form): The geometric shape of a well-formed crystal.
- Crystal Structure (lattice): The regular, repeating arrangement of atoms in a mineral.
- Crystal Systems: Categories of crystals based on symmetry.
- Crystalline: Composed of crystals or related to them.
- Defect: An imperfection or deviation from an ideal crystal lattice.
- Doubly Refractive (anisotropic): Different physical/optical properties in different crystal directions.
- Glassie: A well-shaped, transparent octahedral diamond.
- Glide Plane: The surface a dislocation moves within a crystal, causing an offset.
- Graining (Grain Lines): Visible shadow-like lines on diamond caused by glide planes.
- Growth Marks: Features on a crystal reflecting its growth.
- Habit: Characteristic shape or form of a mineral crystal.
- Line Defect (Dislocation): An imperfection in the crystal lattice along a line.
- Macle: A flat, triangular twinned diamond crystal.
- Octahedron: A crystal shape with eight equal triangular faces.
- Point Defect: An imperfection in the crystal lattice at a single atom position.
- Resorption: The partial dissolving of a diamond's outer surface.
- Singly Refractive (Isotropic): Same physical/optical properties in all crystal directions.
- Specific Gravity (SG): Ratio of a material's weight to an equal volume of water.
- Spectroscopy: The study of matter's interaction with light.
- Strain: Distortion or deformation in a crystal.
- Stress: Force causing crystal distortion.
- Surface Graining: Colorless lines on a diamond's surface.
- Tetrahedron: Diamond structure involving five carbon atoms.
- Trace Elements: Atoms not essential to a gem's composition.
- Trigon: A triangular depression/protrusion on a diamond's faces.
- Twinned Crystal: A crystal formed from two or more parts with shared planes.
- Unit Cell: The smallest repeating group of atoms in a crystal structure.
- Vacancy: A point defect where an atom is missing from its lattice position.
- Volume Defect: Aggregates of atoms or vacancies creating irregularities in the crystal lattice.
Diamond Key Concepts
- Covalent Bonds: Strongest atomic bonds.
- Diamond Habit: Most common is octahedron, but perfect is rare.
- Diamond Defects: Common and not always undesirable.
- Diamond Defects (Categories): Point, line, and volume.
- Mineral Inclusions & Voids: Examples of volume defects.
- Nitrogen & Boron: Foundation of diamond type classification, determined by their presence in the lattice.
- Type I Diamonds: Contain nitrogen atoms replacing carbon in their lattice.
- Type IIa Diamonds: No easily measurable nitrogen or boron impurities.
- Type IIb Diamonds: Contain boron atoms and some nitrogen.
- Diamond Type Identification: Spectroscopy is a reliable method.
- Diamond Crystal Planes: Cubic, octahedral, and dodecahedral planes.
- Diamond Cleavage: Octahedral planes are cleavage planes.
- Diamond Shape and Cut: Shape is crucial for value and cuttability.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
This quiz covers essential concepts related to crystal properties, including definitions of key terms such as aggregate, cleavage, and crystal structure. Test your understanding of how crystals are formed and classified based on their unique attributes. Ideal for students studying mineralogy or geology.
