Agate stone

Etymology and history
Stone was called by the view of Theophrastus, the Greek philosopher and naturalist, who discovered the stone along the shore of the river Achates (Greek: Ἀχάτης) sometime between 3 and 4 centuries before the birth. [2] and other garnet colored chalcedonies and get more than 3000 years ago from the river Achates, now called Dirillo, in Sicily [3].
 Use the old
Garnet is one of the most common materials used in the art of carving hardstone, and was found on a number of archaeological sites, pointing to its use on a large scale in the ancient world, for example, recovery of ancient Knossos site on the island of Crete and clarify its role in the Bronze Age Minoan culture. [4]
 The formation and properties Garnet ranges (such as carnelian, garnet), and the sample is 2.5 cm (1 inch) wide

He also spoke most agate nodules in volcanic rocks or ancient lava, where they represent cavities originally produced by the disengagement of volatile matter in the cluster, which was filled with molten and then, in whole or in part, through the siliceous matter deposited in regular layers on the walls. Such as garnet, when cutting the supply side, displaying a series of parallel lines, often tenuity extreme poverty, giving the appearance of bands to the section. Known stones such as carnelian, ranges, [Riband] and the outline of garnet garnet. 

In the formation of an ordinary agate, it is possible that the water containing silica in a solution that caused, perhaps, of decomposition of some of the silicate in the lava itself, percolated through the rock and deposited paint trays in the interior of vapor - the vesicles. In the nature of the solution or changes in circumstances may cause a corresponding difference in the deposition of successive layers, so that gangs often work agate with layers of quartz crystals. Steam - vesicles may unite while many of the rock is still sticky, and thus shaped like a bowl large, which could become the home of a garnet and the size of an exceptional and, thus, the Brazilian geode lined with amethyst and weighing 67 tonnes has been featured in the exhibition Düsseldorf in 1902. Perhaps a comprehensive review of most of the garnet chemistry is the text of an interview Moxon listed below. 

The first deposit on the wall of the cavity, and the formation of skin, "from" garnet, is generally a dark green metal material, such as celadonite, delessite or "green earth", which are rich in iron probably derived from the decomposition of Augite easier in volcanic rocks and. This green silicate may give rise to a result of the change to brown iron oxide (limonite), and produces the appearance of rust on the outside of the faith, Garnet. Outer surface, freed from its matrix, often revolve garnet and rough, apparently as a result of removing the original paint. The spread of the first layer on the wall of the cavity has been called "," building on this base zeolitic minerals may be deposited priming.
Garnet many hollow, since deposition has not started yet enough to fill the cavity, and in such cases from the date of deposit of the last usually consists of quartz, often amethyst, and after the peaks of crystals oriented free-space and form a crystal lined cavity, or the geoid.
The dissolution of the matrix, which is an integral part of Garnet, they are set free. Garnet and very resistant to weathering and remain as nodules in the soil or gravel and shall be deposited in waterways and beaches. [Edit] Types of agate Agatized coral. "Agate Turritella" (Elimia tenera) of the formation of the Green River, Wyoming 

Garnet and Mexican, showing only one eye, has received the name of the giant agate. Include the issue of green and gold, red, black or color, or other groups as an integral part of agate and disposed of yarn and other forms suggestive of vegetable growth, is of dendritic or moss agate. Dendritic agate Fern in such patterns formed due to the presence of iron oxides and manganese. There are other types of substances deposited through the construction of garnet growth rates include sagenitic (radial mineral crystals) and chunks of debris trap (such as sand and ash, or mud). Garnet in some cases fill the void left by decomposed plant material such as a limb or tree root and is called agate cast party because of his appearance. 

Turritella Agate and consists of silicified fossil tenera Elimia (a mistake Turritella) shells. E.. tenera is a cycle of marine molluscs and a elongated, shells composed of many spiral whorls. Similarly, coral, petrified wood or other organic remains porous rocks can also become agatized. Often referred to is Agatized reefs and Petoskey stone or agate.
Garnet is the Greek name given to the color white to pale tan agate found in Sicily back to 400 BC the Greeks used to make jewelry and beads. Called on any of the garnet and the color of the island of Sicily, once the ancient Greek colony, Garnet Greek. However, it was the stone has been around for centuries before that, and was known to the Sumerians and Egyptians alike, who used the stones for decoration and religious ceremony.
Another type of agate, carnelian, Brazil, which is found as the geoid large nodule layers. Occur in these tunes interlayered brown with white and gray. Forms of quartz within these nodules, and create a model beaten when cut against the axis of growth layers. And often dyed different colors for decorative purposes.
Some of the stones, when examined in thin sections of the transmitted light, show a diffraction due to the sensitivity of the bands in a row, as it is called agate rainbow. Garnet and often coexists with layers or masses of agate, jasper or crystalline quartz due to the different environment during the process of formation.
Other forms of agate include the Lake Superior agate, carnelian (usually in the gallery forms a reddish), Botswana agate, carnelian Ellensburg blue, blue agate lace, feather agate, carnelian tube (with the influx of visible channels), garnet enrichment (who has little or an integral structure), garnet-fire (which seems to glow internally, such as agate and carnelian Mexican lace insane (exhibitions colored complex, and often colorful style ranges), also called the Rodeo Agate Rosetta Stone, which he had based on the mine at that time. [Edit] Uses in industry and art Faceted Botswana Agate
Agate industry is mainly used to make ornaments such as pins, brooches, knives, and paper, inkstands, marble and seals. Because of the hardness and the ability to resist acids, agate is used to make mortars and pestles to crush and mix chemicals. Due to the high polish possible with agate used for centuries for leather polishing tools. Idar - Oberstein was one of the centers that have benefited from Garnet on an industrial scale. Where in the beginning and found locally and used agate to make all types of objects for the European market, and these acts of globalization in all parts of the beginning of the 20: Idar - Oberstein imported large quantities of agate from Brazil, it is also ballast the ship. Using a variety of property, and the chemical processes that industry produces colored beads that have been sold all over the world. [5] was Garnet has long been used in the arts and crafts. Campus of the Presbyterian Church in Yachats, Oregon, and windows with six parts are made of agate that has been collected from local beaches. [6]