You might also like: | All About Jewels: Crystal Systems | Today's featured page: Inventors and Inventions from France |
Our subscribers' grade-level estimate for this page: 9th - 10th or higher |
Rock and Mineral Dictionary |
A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z |
System | Number of Crystallographic Axes | Number of Planes of Symmetry | Number of Axes of Symmetry | Center of Symmetry | Refractivity | Shapes | Gems |
---|---|---|---|---|---|---|---|
Cubic systems | 3 crystallographic axes (of equal length) at right angles to each other | 9 | 13 axes (3 tetragonal, 4 trigonal, 6 digonal) | Yes | singly refractive | diamond, garnet, spinel | |
Tetragonal systems | 3 crystallographic axes at right angles to each other - two of equal length, one longer or shorter | 5 | 5 axes (4 tetragonal, 1 trigonal) | Yes | doubly refractive | rutile, idocrase, zircon | |
Hexagonal systems | 4 crystallographic axes, three of equal length, intersecting at 60 degree angles, the other three are longer or shorter and perpendicular to the first three | 7 | 7 axes (1 hexagonal, 6 digonal) | Yes | doubly refractive | 6-sided prism terminating in a single face | apatite, aquamarine, emerald |
Trigonal systems | 4 crystallographic axes, three of equal length, intersecting at 60 degree angles, the other three are longer or shorter and perpendicular to the first three | 3 | 4 axes (1 trigonal, 2 digonal) | Yes | doubly refractive | quartz, ruby, sapphire, tourmaline | |
Orthorhombic systems | 3 crystallographic axes of different lengths at right angles to each other | 3 | 3 axes (3 digonal) | Yes | doubly refractive | - | chrysoberyl, peridot, topaz |
Monoclinic systems | 3 crystallographic axes of different lengths, 2 at right angles to each other, the third at a different angle | 1 | 1 axis (1 digonal) | Yes | doubly refractive | brazilianite, kunzite, moonstone, jade (nephrite, jadeite), malachite, sphene | |
Triclinic systems | 3 crystallographic axes of different lengths, all at different angles | none | none | Yes | doubly refractive | - | amazonite, axinite, Labradorite, rhodonite, turquoise |
Rock and Mineral Dictionary |
A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z |
Enchanted Learning®
Over 35,000 Web Pages
Sample Pages for Prospective Subscribers, or click below
Overview of Site What's New Enchanted Learning Home Monthly Activity Calendar Books to Print Site Index K-3 Crafts K-3 Themes Little Explorers Picture dictionary PreK/K Activities Rebus Rhymes Stories Writing Cloze Activities Essay Topics Newspaper Writing Activities Parts of Speech Fiction The Test of Time
|
Biology Animal Printouts Biology Label Printouts Biomes Birds Butterflies Dinosaurs Food Chain Human Anatomy Mammals Plants Rainforests Sharks Whales Physical Sciences: K-12 Astronomy The Earth Geology Hurricanes Landforms Oceans Tsunami Volcano |
Languages Dutch French German Italian Japanese (Romaji) Portuguese Spanish Swedish Geography/History Explorers Flags Geography Inventors US History Other Topics Art and Artists Calendars College Finder Crafts Graphic Organizers Label Me! Printouts Math Music Word Wheels |
Click to read our Privacy Policy
Search the Enchanted Learning website for: |