出土古玉的色變__沁色

古玉十三彩 ：
中國人愛玉也喜歡玩玉，其中一個原因就是玉擁有多變的色澤變化，尤其是出土玉的變化程度，更能讓愛好者有莫名成就感的驕傲。因為《古玉出土》【經過人體的盤玩】，其體內的物質成分在受到人氣的涵養後，《玉性又會慢慢復甦》，從而使古玉原先的沁色發生奇妙的變化，呈現出五光十色的豐富色澤。玉的原色在尚未入土前大約有白、黃、青、碧、灰、黑等顏色。而若是經過河水長期滾動的水產玉，則在其外表上常會多一層厚薄不一的《黃褐色》的皮殼，有就是人稱的《玉皮》。
相較於玉的原色，出土古玉的色澤變化就顯得更豐富多采多姿了。古玉長年被埋藏於地下，受地熱、地質、物質、壓力、水氣、各式礦物質等影響，造成玉質受沁產生顏色和質地的改變，不同沁色的礦物質和條件就會讓古玉產生不同的色澤。古玉受浸色變之說，自『明代曹昭』的《格古要論》以來，不斷有人進行著書研究和考證，所論浸色多達80餘種，不過行業內把它總稱為古玉十三彩。就是
陳墨黑、
秋葵黃、
鸚鵡綠、
魚腦凍、
棗皮紅、
茄皮紫、
蝦子青、
松花綠、
雞骨白、
牛毛紋、
鷓鴣斑、
釘金沁、
黑漆古等。
其中以白色、褐色、綠色、黑色的沁色最為常見。
白色沁色：
就是俗稱的「白化」、「鈣化」、「石灰沁」，顧名思義也就是玉器的顏色變白了，這是軟玉色變最普遍的現象。有些白化嚴重者連軟玉原有的透明度都會失去了，造成整體玉質變脆、不透明，而成為十三彩中「雞骨白」。
白化的嚴重程度與年代『並無絕對』的關係，因為一些清代出土的全器深度白化軟玉，就比一些年代久只有局部白化的軟玉來得嚴重。
有關玉器白化的原因，雖然有許多學者進行研究，不過立論卻甚多且雜，目前尚未有一個切確的結論。眾多的立論包含受相鄰之松香、石灰浸入玉中；受《強鹼環境》造成；受《火燒》或曾處在超過900℃以上的地層中；玉器中的《鈣與碳酸氣》結合形成碳酸鈣而析出，產生「脫鈣」現象；玉質結構《變鬆》導致喪失透明度及褪色變白，如同《水與冰》的道理；土壤中《氫氟酸》含量較高…等等。
褐色沁色：
出土玉器為何變成紅褐色的成因，通常認為是玉器與一同入土的鄰近《鐵器》產生作用，鐵離子沁入玉中，而呈現《紅褐色》，也就是俗稱的「鐵沁」。在眾多的考古資料中與鐵器鑲嵌在一起的玉器，往往具有《紅褐色》的色變，就是鐵沁很好的證明。
綠沁色：
玉器色變成綠色的成因，與變褐色一樣，都是入土時被鄰近的《銅器銅離子》沁入玉中而產生變化的。
黑沁色：
入土玉《變黑色》也就是俗稱的《水銀沁》，不過近來的研究資料顯示，水銀沁和我們以往認知是被水銀沁入有很大的誤差。因為水銀本身的比重大於玉的密度，所以玉石是《不可能》把吸收水銀進去的，比較有可能是因為和鄰近的《銀器》產生作用。
觀察古玉的沁色可以發現，最容易發生沁色的位置在《玉器的邊緣地帶》，因為該位置比較接近玉璞，其結構較為《疏鬆》，所以比較容易吸入其他礦物質產生變化。
由於入土玉在墓葬時的環境變數實在太多了，與玉器接觸的物體如泥土、銅器、鐵器、漆器、絲綢、陪葬品…等，或是潮濕、乾燥、水浸、冷熱的地層環境都會造成玉質的變化，所以玉器沁色才會如此豐富多彩，而盤玩、欣賞時也才能產生各式各樣的推敲玩味.
Ancient Jade thirteen color: ( translated by google)Chinese people love jade like jade, one of the reasons jade have varied color and  changes, especially changes of buried jade, inexplicable sense of accomplishment and allow the fans proud. Because the "jade discovery"  through the body plate, the material composition of the body in the popular conservation were after, "jade sex will slowly recover," so that the original impregnation jade wonderful changes occurred, showing a colorful rich color. Jade has not been buried in front of color around the white, yellow, green, Bristol, gray, black and other colors. And if after a long scroll of the river fish jade, its appearance in more than a layer of varying thickness often the "brown" of the hull, there is called the "jade skin."Compared to the color of jade, earth buried jade  color change becomes a more abundant colorful. Jade long been buried in the ground by geothermal, geological, physical, pressure, water vapor, and other kinds of minerals, creating a jade color and texture produced by the Qin changes, different impregnation of mineral and conditions will allow Jade produce different colors. Jade mere mention of the baptism, said that since the "Ming Cao Chao" and "grid to the ancient theory" has been some research and write books for research, the theory of color up to 80 kinds of dip, but the industry as it always Jade thirteen color. Is
Chen ink black,Okra yellow,Parrot green,Fish brain freeze,Jujube skin red,Eggplant Purple,Shrimp green,Pin flower green,Chicken bone white,Ox hair pattern,Partridge spot,Golden impregnation nails,Old black and so on.Among them, white, brown, green, black impregnation of the most common.
White impregnation:Is commonly known as "bleaching", "calcification", "lime Qin", by definition is the color of white jade, this is the most common soft pale jade phenomenon. Some severe cases, even the albino transparency of the original nephrite are lost, resulting in an overall qualitative change in crisp jade, opaque, and become a thirteen color in the "chicken bone white."Bleaching severity and age "there is no absolute" relationship, because some of the depth of the Qing Dynasty unearthed in full control albino nephrite, a number of years longer than the soft jade only partial albinism is more serious.The jade albino reason, although many scholars to study, but the arguments are many and complex, yet there is indeed a cut conclusion. Adjacent to a large number of arguments that contain the rosin, lime jade immersion; by the "alkali environment" cause; by the "fire" or has more than 900 ℃ in 超过 formation; jade in the "calcium and carbonic acid gas" to form precipitation of calcium carbonate to produce "demineralized" phenomenon; jade structure "loose" causing the loss of transparency and fading white, as "water and ice," the truth; soil "hydrofluoric acid" with higher levels of ... and so on.
Brown impregnation:Why become a jade unearthed the cause of red-brown, usually considered to be buried with jade with the adjacent "iron" to be effective, iron Qinru jade, while showing the "red brown", also known as "iron Qin." Among the many archaeological data with iron inlaid with jade, often with a "red brown" and discoloration, iron Qin is a good proof.
Green impregnation:Jade green color into the causes, and become brown, are buried nearby when the "bronze copper ions" Qinru jade resulting change.
Black impregnation:Buried jade "change the black" is commonly known as "mercury Qin", but recent research data shows that mercury Qin and our knowledge is the past, mercury Qinru a great error. Because mercury is greater than their proportion of the density of jade, jade is so "impossible" to absorb the mercury inside, the more likely because of and adjacent to "silver" to be effective.Observe the color of jade can be found in Qin, the most vulnerable position in the impregnation of the "jade edge" because the location is closer Yupu, its structure is relatively "loose", it is more likely to produce changes inhalation of other minerals.Because buried jade burial environment variables when too many, contact with objects such as soil jade, bronze, iron, lacquer, silk, grave goods ... and so on, or wet, dry, flooding, hot and cold environment will result in the formation Jade qualitative change, so will be so colorful jade impregnation, and set to play, to enjoy when they can produce all kinds of scrutiny interesting.