Cleaving veins: The cleaving veins seen inside the jade artifact are caused by the interaction of physical forces from heat and pressure on the jade. They are different from the cracks caused by percussion. Exterior cracks are common phenomena for cracks caused by percussion. Usually, there are no exterior cracks for cleaving veins.冰裂紋：是因玉質本身在內部應力作用下產生的綹裂，在自然環境中年深日久的作用下，加之其他物質緩慢浸染，綹裂紋會日漸明顯，顏色也會逐漸加深，有向周圍擴散的現象。沁紋多呈凹陷現象，邊緣呈鋸齒狀。這種冰裂紋目視可見，撫之無痕，走向呈斜開片，邊緣圓鈍，撫之無刺手感覺，看不出明顯的縫隙。

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