翡翠鑑別
翡翠起膠係咩感覺？點樣識別有起膠嘅翡翠？
What Is the Jelly Effect in Jadeite? How to Identify It
起膠係老坑翡翠獨有嘅視覺特徵，係判斷翡翠係咪老坑料嘅重要指標。呢篇文章詳細解釋起膠嘅成因、視覺特徵，同點樣用肉眼識別。
'起膠'係翡翠行業用語，形容老坑翡翠獨有視覺效果嘅術語。有起膠感嘅翡翠，光線在表面形成柔和嘅漫反射，整體散發出一種溫潤、有深度嘅光感，就像果凍或膠質物體一樣。呢種效果係老坑翡翠晶體結構細膩緊密嘅直接體現。
起膠嘅成因
起膠嘅根本原因係翡翠晶體結構嘅緊密程度。老坑翡翠嘅晶體顆粒極為細小，排列緊密有序，晶體之間幾乎冇縫隙。當光線照射到呢種結構時，光線唔會直接反射（鏡面反射），而係在晶體之間發生多次散射，形成柔和嘅漫反射效果。呢種漫反射就係我哋眼中嘅'膠質感'。
起膠嘅視覺特徵
- 光澤柔和：唔係鏡面反射，而係整體散發出溫潤嘅光感
- 有深度感：光線似乎可以進入翡翠內部，而唔係只停留在表面
- 溫潤感：視覺上有一種'包裹感'，令人感覺翡翠係活嘅
- 移動時光感變化：轉動翡翠時，光感會隨角度變化，但始終保持柔和
- 無刺眼感：即使在強光下，起膠嘅翡翠也唔會有刺眼嘅強反光
起膠 vs 起鋼光
起膠同起鋼光係兩種唔同嘅光澤類型，唔係高低之分，而係種水類型嘅分別。起鋼光主要出現在玻璃種翡翠（最高種水），光澤銳利集中；起膠主要出現在糯種至糯冰種嘅老坑翡翠，光澤柔和溫潤。兩種都係高品質老坑翡翠嘅特徵，只係種水等級唔同。
點樣識別有起膠感嘅翡翠？
- 在自然光下觀察：自然光最能展現起膠效果，避免在強烈燈光下判斷
- 轉動翡翠：觀察光感係咪柔和而有深度，而唔係銳利嘅鏡面反射
- 對比觀察：將有起膠感同無起膠感嘅翡翠放在一起，差別會非常明顯
- 感受溫潤感：起膠嘅翡翠在視覺上有一種'活'嘅感覺，新坑料則顯得呆板
💡 行家口訣：有起膠感嘅翡翠，係老坑料嘅重要標誌之一。如果一件翡翠有起膠感，基本可以確定係老坑料，品質相對有保障。
English Version
What Is the Jelly Effect in Jadeite? How to Identify It
'Jelly effect' (起膠) is a trade term describing a visual quality unique to old-mine (老坑) jadeite. When a piece of jadeite has the jelly effect, light forms a soft, diffuse reflection on the surface — the stone radiates a warm, deep glow, like jelly or a gel substance. This effect is a direct expression of the extremely fine and tightly interlocked crystal structure of old-mine material.
The Cause of the Jelly Effect
The jelly effect originates from the density of the jadeite's crystal structure. Old-mine jadeite has extremely fine crystal grains that are tightly interlocked with almost no gaps between them. When light strikes this structure, it does not reflect directly (specular reflection) but instead scatters multiple times between crystals, producing a soft, diffuse reflection. This diffuse reflection is what we perceive as the 'jelly-like' quality.
Visual Characteristics of the Jelly Effect
- Soft lustre: not a mirror reflection, but a warm, enveloping glow from within
- Sense of depth: light appears to enter the stone rather than simply bounce off the surface
- Warmth: a visual 'wrapping' quality that makes the stone feel alive
- Shifting light as the stone rotates: the glow changes with angle but always remains soft
- No harsh glare: even under strong light, jelly-effect jadeite never produces harsh reflections
Jelly Effect vs Steel Gloss
The jelly effect and steel gloss are two different lustre types — not a hierarchy, but a difference in quality category. Steel gloss appears primarily on glass-type jadeite (the highest grade), with sharp, concentrated reflections. The jelly effect appears primarily on nuo-type to nuo-ice-type old-mine jadeite, with soft, warm luminosity. Both are hallmarks of high-quality old-mine jadeite — they simply represent different grade levels.
How to Identify Jadeite with the Jelly Effect
- Observe in natural light: natural light best reveals the jelly effect; avoid judging under harsh artificial lighting
- Rotate the stone: check whether the glow is soft and deep rather than a sharp mirror reflection
- Compare side by side: placing jelly-effect and non-jelly-effect pieces together makes the difference immediately obvious
- Feel the warmth: jelly-effect jadeite has a visual 'aliveness' that new-mine material lacks
💡 Trade wisdom: The presence of the jelly effect is one of the key markers of old-mine material. If a piece of jadeite shows the jelly effect, it can generally be confirmed as old-mine origin — a strong indicator of quality.