RI020 Obsidian

Class: 4E
Name: Ng Hoi Ching
Year: 2014 – 2015
地質年代:(化石) (岩石)

 

Geological Age: (Fossil) (Rock)

 

形成:(岩石) (礦物)

原生物:(化石)

黑曜石是一種天然玻璃。在地下深處的高壓之下,流纹岩質熔岩可以含有高達10%的水分,這幫助它甚至在低温下也能保持液體状態。噴發到地表時,因地表壓力低,揮發性的水分得以迅速釋放,從而增加了熔浆的黏度。熔浆黏度增加卻妨礙了结晶作用,於是熔岩凝固成為玻璃。不同的黑曜石由不同的结晶物質組成。

Formation:(Rock) (Mineral)

Living Specimens: (Fossil)

Obsidian is a kind of natural glass. Under the high pressure of underground, Rhyolite lava can contain up to 10% water, this help lava remains liquid under low temperature. When it is erupted to the ground surface, due to the low pressure of ground surface, the water can be released rapidly.

特性:

除含少量斑晶、雏晶外,黑曜石幾乎全由玻璃貭組成。黑色或黑褐色致密块狀,有時見石泡構造。玻璃光澤明顯,具貝殻斷狀口。因為石體結晶的原因,大部分呈深綠至黑色。少部分也會有紅色和黃色的例外。天然黑曜石在陽光下會有「彩眼」效果。

Properties:

In addition to containing a small amount of phenocryst and crystallite, Obsidian is almost entirely composed of glass. Black or dark brown dense block, sometimes it can be lithophysa structure Glasses luster with conchoidal fracture. Because of the ore body crystallization, most obsidian are dark green to black. Few exceptions will have the red and yellow colors. Natural Obsidian can have the “eye” effect under the sun.

用途:(岩石) (礦物)

黑曜石具備玻璃的特性,敲碎后斷面呈貝殻斷狀口,十分鋒利。逺古石器时代曾被用作刀,箭頭等切削用具,現代人利用黑曜石来制作外科手術用解剖刀的刀片。黑曜石可作装飾品和工藝品的原料。

Application: (Rock) (Mineral)

Obsidian have the properties of glass, conchoidal fracture will appear when they are broken, which are very sharp. In the Ancient Pala eolithic, it was used as a sword, arrow or a cutting tool, while the modern people using obsidian to make surgical scalpel blade Obsidian can be decorations and crafts materials.

分佈:(岩石) (礦物)

有或曾有火山活動的地區

土耳其東南部

Distribution: (Rock) (Mineral)

It is mainly located in the central and the eastern part of Turkey. In the Central Anatolia, obsidian can be found in Bogazkoy, Bekarlar and Karakaya etc. Besides, on the eastern part of Anatolia, Erzurum, Pasinler and Rize are places that obsidian can be found