How red agate is formed

Agate is mainly produced in volcanic fissures and cavities, but also in sedimentary rock layers. The world's most famous places of origin are India, Brazil and other places. China's agate origin is widely distributed, almost all provinces, mainly in Heilongjiang, Liaoning, Hubei and other regions. Nanjing Yuhuatai output of rain flower stone is a kind of agate. Ancient legend agate is condensed by the so-called ghost blood, but also just a legend.

Agate because of the beautiful grain band, since ancient times has been used by people to decorate. Unearthed jade, common strings of agate beads, to the necklace is more.

China's ancient books about agate records are many. Before the Han Dynasty, agate was also known as "agate" or "red jade". "Guangya" has "agate stone second jade" and "jade red first Qiong" said. The term "agate" comes from the Buddhist scriptures. Sanskrit name "Asmagapo", meaning "agate", visible after the introduction of Buddhism into our country, Jade or red Qiong only in our country renamed "agate".

Composition of agate fine minerals in addition to chalcedony, sometimes also see a small amount of opal or cryptocrystalline particulate quartz. Strictly speaking, there is no banding pattern features, can not be called agate, can only be called chalcedony. Now on the market some of the chalcedony without patterned grain also known as "agate", which with the meaning of the ancient agate is not consistent. Agate pure white, because of other metal elements (such as Fe, Ni, etc.) appear gray, brown, red, blue, green, emerald green, pink green, black and other colors, sometimes several colors mixed or intermittent. Agate blocks are transparent, translucent and opaque, with a glassy to waxy luster. Hardness 6.5 ~ 7, specific gravity 2.65.

Agate according to its banding pattern of thickness and morphology has many varieties. Banded "onyx" is called "onyx", which has a red band of the most valuable, known as "red onyx". In addition, there are "banded agates", "castle agates", "bluish agates", and "moss agates", Can I get the "Kinko Agate", "Hopi Agate", "Miso Agate", "Kashiwa Agate", "Kashiwagi Agate", "curved agate", "water gall agate" and other varieties (see Li Shizhen, "Compendium of Materia Medica").

In the absence of patterned "chalcedony", there are also many jade raw materials. According to the different colors, there are "red chalcedony", "green chalcedony" (also known as Inka stone), "onion green chalcedony", "blood chalcedony " (also known as bloodstone) and "jasper" and so on.

Agate, like nephrite, is also a traditional jade in China. Agate cups and agate beads were among the jade objects unearthed at sites such as Beiyinyangying in Nanjing. Among a large number of agate beads, there is one in the shape of an evil-doer, 1.7 centimeters long. Agate beads have also been found at Yongjing Dahozhuang Qijia culture site in Gansu, at the spring and autumn tombs in Dadian, Junan, Shandong, and at the Eastern Jin Dynasty tombs in Xiangshan, Nanjing.

Ancient agate both from the Western region, India, Persia, Kang, Japan and other countries of the tribute, but also produced from the domestic territory. Such as the Northeast Fuyu and Yilou, the former rule in present-day Jilin Siping City; the latter is the name of the ethnic group, living in the north of the Changbai Mountains, the Songhua River, the lower reaches of the Heilongjiang River, where from ancient times to out of the "red stone" enjoys the name (see the "Book of the Later Han Dynasty - East Barbarians biography"). In addition, Weizhou (now Weixian) Jukongshan and Xuanfu (Xuanhua), Sijiaoshan (see "Heavenly Creatures"), Gansu and Ningxia area (see "Museum"), Shenmu and Fugu area of Shaanxi Yan'an Province (see "GuangYiJi"), RuZhou Chiling Town (see "Song Shi"), Guangxi Zhuang Autonomous Region, BoBai County (see "BoBai County Zhi"), Nanjing Yuhuatai (see "Precious Games continued to test"), etc., are all produced agate. Nowadays, China's geologists in the northwest, north, northeast and southwest, south China, many areas have proved the origin of agate. Ancient and modern, because agate origin, so identify the source of jade material unearthed agate is not that easy. Such as the famous Tang dynasty animal head agate cup, the source of its jade can not figure out.