客戶送驗一個有證書的天然黃寶石至台灣聯合鑑定中心，據聞為天然色黃寶石，但經過本所三位鑑定師以拉曼光譜和顯微鏡確認後，證實為鈹擴散處理的橙黃色剛玉。鈹擴散是一種以天然金綠寶石(鋁酸鈹BeAl2O4)和剛玉(氧化鋁Al2O3)為原料的深度擴散處理，由於天然的黃寶石主要由鐵產生顏色，而鐵不像鈦和鉻能透過一般的加熱擴散進入剛玉晶格，所以早期天然黃寶石產量極為有限且不易熱處理處理增色。後來在偶然的熱處理意外中，泰國寶石商發現加了鈹的熱處理可以為剛玉帶來一種黃-橙色的增色效果，且若以淡粉紅色剛玉處理，甚至可以得到粉橙色的蓮花藍寶(Padparadsch)，這就是鈹擴散處理的由來。檢驗鈹擴散除了需要高倍率的顯微鏡與觀察經驗外，更需要拉曼光譜或甚至雷射誘導擊穿光譜等高階儀器。想瞭解更多藍寶石的優化處理嗎，請參閱實用寶石學一書，剛玉一節。
A certified natural yellowish orange sapphire is sent to TULAB, and it is claimed to be natural color without Be-diffusion treatment. TULAB gemologist confirm the sapphire to be be-diffusion treated sapphire with raman spectrum and magnification test. Be-diffusion is bulk diffusion which use corundum and chrysoberyl as raw materials. Yellow sapphire is not easy to enhance color by simple heating; however, with the Be-diffusion method, colorless sapphire will turn to yellow or orange color. Evenmore, natural pink sapphire can be enhanced to orangey pink sapphire which is commercially named as “Padparadsch” with be-diffusion treatment. Besides gem microscope, high-tech instruments such as raman analyzer or LIBS is essential for Be-diffusion testing.
鈹擴散黃寶石
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