Calcification:

The phenomenon of calcification is believed to be caused by decomposing the structural water of the jade. The cause of decomposition may be from the interaction of heat and the pressure of the environment where the jade is buried.  Another explanation is that calcification is caused by the interaction of the jade and the surrounding calcium where the antique jade buried. Most people tend to in favor of this kind explanation of jade calcification before any scientific proof has been found. It should be noted that fake calcification jades are often found to fake Liangzhu Culture jades. The faking technique is to form a coating layer on inferior jade or fabricated jade to imitate the calcification appearance that looks like the Liangzhu Culture jades.所謂鈣化是玉器在上千年的埋藏中發生的質變現象，究其原因有地熱說、火燒說等多種，目前暫無定論，但鈣化之處玉質發生質的變化是肯定的。自出現仿古玉以來，人們經常會利用玉皮、僵、火燒等方法仿鈣化。

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