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
| A | |
| agate |
A form of quartz that has microscopic crystals. Agates are formed in cavities where layers of silica and other elements are deposited by water. Once the water has evaporated, a layer of agate remains. Through the repetition of this process, bands of different colors are deposited to form the agate. Although it does not have bands of color, moss agate is grouped with the agates because of a similar composition.
(Agate Products) |
| amazonite |
A form of microcline feldspar with a blue-green color.
(Amazonite Products) |
| angelite |
A light blue form of calcium sulfate (CaSO4) that does not contain water (anhydrous). Because of this property, angelite is often called anhydrite.
(Angelite Products) |
| B | |
| basalt |
A volcanic igneous rock that commonly covers the floor of the ocean. Water can be trapped in the process of forming basalt, thus producing a rock with many holes. |
| brecciated jasper |
A form of jasper with a brick red color and black lines.
(Brecciated Jasper Products) |
| C | |
| caldera |
An indentation in the Earth which is formed by a collapse after a volcanic eruption. When magma is rapidly ejected from beneath the surface of the Earth, an empty cavern is left behind. The weight of the lava above the surface can cause this empty space to collapse. |
| Camo Stone (TM) |
A form of jasper with green and yellow coloration.
(Camo Stone (TM) Products) |
| cat's eye |
A stone with a property called chatoyancy. Chatoyancy occurs when light is reflected from microscopic inclusions within the stone. A single band is the cat's eye effect. The cat's eye jewelry on Crafted By Kate are made from glass.
(Cat's Eye Products) |
| coral |
A piece of calcium carbonate skeleton which is built up by corals living underwater. Many coral skeletons bleach out to white, so most colored coral on the market tends to be dyed.
(Coral Products) |
| Crazy Horse Stone (TM) |
A form of limestone that generally has a greyish shade with streaks of pink, purple and brown. (Crazy Horse Stone(TM) Products) (About Crazy Horse Stone(TM)) |
| crystal |
A solid material which is made up of elements arranged in a repeating pattern. It is possible to see the effects of the repeating pattern in common table salt, which is a crystal made up of repeating elements of sodium (Na) and chlorine (Cl) in a one-to-one ratio. |
| D | |
| E | |
| extrusive rock |
A rock that was formed when magma flowed to the surface of the Earth so the lava solidified above the ground. (obsidian, rhyolite, basalt) |
| F | |
| feldspar |
A member of the silicate family which contain aluminum and often potassium, calcium or sodium. The pink color in granite is due to a feldspar. |
| G | |
| granite |
An intrusive igneous rock, the magma that forms granite hardens deep underground. The large quantities of granite on the Earth's surface are only accessible because of the erosion of rocks which had previously covered the granite. |
| H | |
| I | |
| igneous rock |
A rock that formed when molten rock solidified. |
| intrusive rock |
A rock that formed when magma (molten rock) solidified underground. (granite) |
| J | |
| jasper |
A form of quartz (a silicate) in the chalcedony family. This form of quartz is called cryptocrystalline because the crystals that make up the rock are microscopic. The color of the jasper depends on which elements other than silicon and oxygen are present. See also: brecciated jasper, CamoTM stone, kambaba jasper, red picture jasper, zebra "jasper"
(Jasper Products) |
| K | |
| kambaba jasper |
A form of jasper which is green with black lines running through it.
(Kambaba Jasper Products) |
| L | |
| lava |
Magma (molten rock) that has reached the surface of the Earth. |
| lava dome |
A mound of igneous rock which is formed when viscous lava hardens as it is flowing, resulting in a pileup of lava on top of itself. |
| lava rock |
Igneous rock which has been formed by lava hardening. The holes present throughout the rock are where water was trapped in the rock as it solidified.
(Lava Rock Products) |
| M | |
| magma |
Molten rock that is underground. Once it reaches the surface, magma becomes lava. |
| moss agate |
A mineral that is a variety of quartz with microscopic crystals. Moss agate contains green or brown inclusions that resemble moss. Since it does not have the banded pattern of agates it is not scientifically an agate, but it tends to be included with them because of the similar compositions.
(Moss Agate Products) |
| N | |
| O | |
| obsidian |
An extrusive igneous rock which tends to be jet black. The glassy texture of obsidian is a result of rapid cooling forming microscopic crystals. |
| onyx |
A variety of agate which has alternating white and black bands. Most onyx is dyed jet black for use in jewelry.
(Onyx Products) |
| P | |
| peace "jade" |
A mixture of serpentine, stichtite and white quartz, peace "jade" is so named because of its resemblance to jade.
(Peace "Jade" Products) |
| phenocryst |
A relatively large crystal that is embedded in an igneous rock. |
| porphyritic |
Rock that contains large embedded crystals. |
| Q | |
| quartz |
A rock containing silicon and oxygen that has a tendency to form large crystals. Most commonly thought of as translucent or white, the color of quartz can vary greatly. |
| R | |
| red picture jasper |
A form of jasper that is red with black lines.
(Red Picture Jasper Products) |
| rhodonite |
A mineral composed of manganese silicate. Rhodonite is a pink mineral ( (Rhodonite Products) |
| Russian serpentine |
A mottled green silicate that is formed by chemical changes in other minerals.
(Russian Serpentine Products) |
| rhyolite |
A volcanic igneous rock that contains inclusions of quartz, feldspar and other minerals. (Rhyolite Products) (About Rhyolite) |
| rhyolitic lava |
Lava that has a high silica (SiO2) concentration. Rhyolitic lava tends to be viscous. |
| S | |
| sanidine |
A volcanic feldspar form of potassium aluminosilicate with often occurs in rhyolite. Some sanidine can be used to make moonstones. |
| serpentine |
See Russian Serpentine
|
| silica |
The chemical compound silicon dioxide (SiO2). Commonly found as sand or quartz, silica is a base for a large variety of minerals in the silicate family. |
| silicate |
A group of minerals that contain silicon and oxygen in a structure with a silicon atom in the center and four oxygen atoms surrounding it. Some of the numerous silicates are: quartz, amethyst, tiger's eye, carnelian, onyx, jasper, agate, opal, feldspar, nephrite (jade), emerald, aquamarine, garnet and topaz. |
| T | |
| U | |
| V | |
| viscous |
A liquid which has a high resistance to flow. Water, for example, flows easily and would have a lower viscosity than molasses. |
| W | |
| X | |
| Y | |
| Z | |
| zebra jasper |
A mineral that is commonly called jasper due to its coloring and properties. Zebra jasper is scientifically classified as onyx marble.
(Zebra Jasper Products) |
