Crystallography and Minerals Arranged by Crystal Form

Amorphous Isometric Tetragonal Orthorhombic Hexagonal Trigonal Monoclinic Triclinic

1. Crystal Groups and Classes - Crystallography groups are composed of 32 classes of symmetry derived from observations of the external crystal form.  From these 32 classes, 230 space groups (see Crystallography 101) are distinguishable using x-ray analysis.  For additional information on crystal systems, please review an excellent on-line treatment of this subject, the Introduction to Crystallography and Mineral Crystal Systems by Mike and Darcy

System (1) Class Name (2)AXES

Planes CenterHermann-Maugin Symbols (3)2-Fold3-Fold4-Fold6-Fold

Isometric

 

 

Tetartoidal 3 4 - - - - 23

Diploidal 3 4 - - 3 yes 2/m 3

Hextetrahedral 3 4 - - 6 - 4 3m

Gyroidal 6 4 3 - - - 432

Hexoctahedral 6 4 3 - 9 yes 4/m 3 2/m

Tetragonal

 

 

 

Disphenoidal 1 - - - - - 4

Pyramidal - - 1 - - - 4

Dipyramidal - - 1 - 1 yes 4/m

Scalenohedral 3 - - - 2 - 4 2m

Ditetragonal pyramidal - - - - 4 - 4mm

Trapezohedral 4 - 1 - - - 422

Ditetragonal-Dipyramidal 4 - 1 - 5 yes 4/m 2/m 2/m

Orthorhombic 

Pyramidal 1 - - - 2 - mm2

Disphenoidal 3 - - - - - 222

Dipyramidal 3 - - - 3 yes 2/m 2/m 2/m

Hexagonal Trigonal Dipyramidal - 1 - - 1 - 6

Pyramidal - - - 1 - - 6

 

 

Dipyramidal - - - 1 1 yes 6/m

Ditrigonal Dipyramidal 3 1 - - 4 - 6m2

Dihexagonal Pyramidal - - - 1 6 - 6mm

Trapezohedral 6 - - 1 - - 622

Dihexagonal Dipyramidal

6 - - 1 7 yes 6/m 2/m 2/m

Trigonal

 

 

Pyramidal - 1 - - - - 3

Rhombohedral - 1 - - - yes 3

Ditrigonal Pyramidal - 1 - - 3 - 3m

Trapezohedral 3 1 - - - - 32

Hexagonal Scalenohedral 3 1 - - 3 yes 3 2/m

Monoclinic 

Domatic - - - - 1 - m

Sphenoidal 1 - - - - - 2

Prismatic 1 - - - 1 yes 2/m

TriclinicPedial - - - - - - 1

Pinacoidal - - - - - yes 1

ISOMETRIC - Mike and Darcy Howard's Details on The Cubic (Isometric) System

Isometric (Cubic) Crystal Classes

Crystal AxesExample

Form

Java Example

Forms and Links to Mineral Listings

Paper Models

IsometricCrystallographi

cAxes

Isometric Minerals Crystal Form Example[214], [104], [024], [100], [010]

Class Unknown Mineral Listing

Isometric Diploidal Mineral ListingH-M Symbol (2/m 3)

IsometricGyroidal Mineral ListingH-M Symbol (4 3 2)

IsometricHexoctahedral Mineral Listing H-M Symbol (4/m 3 2/m)

IsometricHextetrahedral Mineral ListingH-M Symbol (4 3m)

IsometricTetartoidal Mineral ListingH-M Symbol (2 3)

TETRAGONAL - Mike and Darcy Howard's Details on The Tetragonal System

Tetragonal Crystal Classes

Crystal Axes Example Form

Java Example

Forms and Links to Mineral Listings

Paper Models

TetragonalCrystallograp

hicAxes

Tetragonal Mineral Crystal Form Example[214], [104], [024], [100], [010]

Class Unknown Mineral Listing

TetragonalDipyramidal Mineral ListingH-M Symbol (4/m)

TetragonalDisphenoidal Mineral ListingH-M Symbol (4)

Tetragonal Ditetragonal Dipyramidal Mineral ListingH-M Symbol (4/m 2/m 2/m)

TetragonalPyramidal Mineral ListingH-M Symbol (4)

TetragonalDitetragonal-pyramidal Mineral ListingH-M Symbol (4mm)

Tetragonal Scalenohedral Mineral ListingH-M Symbol (4 2m)

TetragonalTrapezohedral MineralH-M Symbol (4 2 2)

ORTHORHOMBIC - Mike and Darcy Howard's Details on The Orthorhombic System

Orthorhombic Crystal Classes

Crystal Axes Example Form

Java Example

Forms and Links to Mineral Listings

Paper Models

OrthorhobicCrystallograp

hicAxes

Orthorhombic Minerals Crystal Form Example[214], [104], [024], [100], [010]

Class Unknown Mineral Listing.

OrthorhombicDipyramidal Mineral ListingH-M Symbol (2/m 2/m

2/m)

OrthorhombicDisphenoidal Mineral ListingH-M Symbol (2 2 2)

OrthorhombicPyramidal Mineral ListingH-M Symbol (mm2)

HEXAGONAL - Mike and Darcy Howard's Details on The Hexagonal System (Hexagonal Division)

Hexagonal Crystal Classes

Crystal Axes Example Form

Java Example

Forms and Links to Mineral Listings

Paper Models

Hexagonal Minerals Crystal Form Example.[214], [104], [024], [100], [010]

Class Unknown Mineral Listing.

HexagonalCrystallograp

hicAxes

HexagonalDihexagonal Dipyramidal Mineral ListingH-M Symbol (6/m 2/m 2/m)

HexagonalDihexagonal Pyramidal Mineral ListingH-M Symbol (6mm)

HexagonalDipyramidal Mineral ListingH-M Symbol (6/m)

HexagonalDitrigonal Dipyramidal Mineral ListingH-M Symbol (6 m2)

HexagonalPyramidal Mineral ListingH-M Symbol (6)

HexagonalTrapezohedral Mineral ListingH-M Symbol (6 2 2)

Hexagonal Trigonal Dipyramidal MineralH-M Symbol (6)

TRIGONAL - Mike and Darcy Howard's Details on The Hexagonal System (Trigonal Division)

Trigonal Crystal Classes

Crystal Axes Example Form

Java Example

Forms and Links to Mineral Listings

Paper Models

TrigonalCrystallograp

hicAxes

Trigonal Minerals Crystal Form Example.[214], [104], [024], [100], [010]

Class Unknown Mineral Listing.

TrigonalDitrigonal Pyramidal Mineral Listing and Stereo image.H-M Symbol (3m)

TrigonalHexagonal Scalenohedral Mineral Listing and Stereo image.H-M Symbol (3 2/m)

TrigonalPyramidal Mineral Listing and Stereo image.H-M Symbol (3)

TrigonalRhombohedral Mineral Listing and Stereo image.H-M Symbol ( 3)

Trigonal Trapezohedral Mineral Listing and Stereo image.H-M Symbol (3 2)

MONOCLINIC - Mike and Darcy Howard's Details on The Monoclinic System

Monoclinic Crystal Classes

Crystal Axes Example Form

Java Example Forms

and Links to Mineral Listings

Paper Models

MonoclinicCrystallograp

hicAxes

β <> 90°

Monoclinic Minerals Crystal Form Example.[214], [104], [024], [100], [010]

Class Unknown Mineral Listing.

MonoclinicDomatic Mineral ListingH-M Symbol (m)

MonoclinicPrismatic Mineral ListingH-M Symbol (2/m)

MonoclinicSphenoidal Mineral ListingH-M Symbol (2)

TRICLINIC - Mike and Darcy Howard's Details on The Triclinic System

Triclinic Crystal Classes

Crystal Axes Example Form Java Example

Paper Models

Forms and

Links to Mineral Listings

TriclinicCrystallographi

cAxes

α,β,γ <> 90

Triclinic Minerals Crystal Form Example.[214], [104], [024], [100], [010]

Class Unknown Mineral Listing.

TriclinicPedial Mineral ListingH-M Symbol (1)

TriclinicPinacoidal Mineral ListingH-M Symbol ( 1)