# Difference between revisions of "Crystal Systems"

Line 18: | Line 18: | ||

| '''Tetragonal''' <br> | | '''Tetragonal''' <br> | ||

− | The tetragonal system also has three axes <br> | + | The tetragonal system also has three axes<br> |

− | that all meet at 90°. It differs from the <br> | + | that all meet at 90°. It differs from the<br> |

− | isometric system in that the C axis is longer <br> | + | isometric system in that the C axis is longer<br> |

than the A and B axis which are the same length<br> | than the A and B axis which are the same length<br> | ||

− | that all meet at 90°. It differs from the isometric <br> | + | that all meet at 90°. It differs from the isometric<br> |

system in that the C axis is longer than the A<br> | system in that the C axis is longer than the A<br> | ||

and B axis which are the same length. | and B axis which are the same length. | ||

| [[image:xl_tetragonal.gif|left|]] | | [[image:xl_tetragonal.gif|left|]] | ||

| [[Zircon]] | | [[Zircon]] | ||

+ | |||

+ | |- | ||

+ | | '''Hexagonal''' | ||

+ | |||

+ | In the hexagonal system we have an additional axes,<br> | ||

+ | which gives the crystals six sides. Three of these<br> | ||

+ | are equal in length and meet at 60° to each other. <br> | ||

+ | The C or vertical axis is at 90° to the shorter axes.<br> | ||

+ | Mineralogists sometimes divide this into two systems, <br> | ||

+ | the hexagonal and the trigonal, based on their external<br> | ||

+ | appearance, as follows: | ||

+ | |[[image:xl_hexagonal.gif|left|]] | ||

+ | |[[Aquamarine]]<br> | ||

+ | [[Benitoite]]<br> | ||

+ | [[Beryl]] <br> | ||

+ | [[Citrine]]<br> | ||

+ | [[Emerald]]<br> | ||

+ | [[Heliodor]]<br> | ||

+ | [[Morganite]]<br> | ||

+ | [[Quartz]] <br> | ||

+ | [[Ruby]] <br> | ||

+ | [[Sapphire]] <br> | ||

|} | |} |

## Revision as of 16:47, 1 October 2006

## Crystal Systems & Forms

Crystal System | Diagram | Examples |
---|---|---|

Cubic The cube is composed of 6 square faces |
Diamond | |

Tetragonal The tetragonal system also has three axes |
Zircon | |

Hexagonal
In the hexagonal system we have an additional axes, |
Aquamarine Benitoite |