本研究以滑石（d50=6.4 μm）、高嶺土（d50=3.1 μm）以及α-Al2O3（d50=253 nm）粉末依照堇青石之計量比混合。經計算三者以1：10.88：3672.55顆數組成約一10 μm之反應單元。另外添加d50為2.5、21.5、44.3 μm堇青石粉末作為晶種，藉此觀察晶種添加對合成堇青石過程過渡相以及堇青石生成量之影響。計算d50為2.5（C2）、21.5（C20）、44.3 μm（C40）晶種的單層披覆量為15、30、55wt%（-15、-30、-55）。研究主要透過DTA、XRD、XRF、SEM、PSD、分析結果。
結果發現，隨晶種變細，α-Al2O3延後消失，由α-Al2O3生成Spinel的過程改為生成Cordierite，即粗晶種（C20 & C40）：α-Al2O3 + Enstatite → Spinel + SiO2，而細晶種（C2）：α-Al2O3 + Enstatite + 3/2 SiO2 → 1/2 Cordierite。相同情況，Mullite則提前結束，由其結晶相消失過程推知：由Mullite為來源的兩個路徑，即添加粗晶種下：Mullite + 3 Enstatite → 3 Spinel + 5 SiO2，而細晶種：Mullite + 3 Enstatite + 5/2 SiO2 → 3/2 Cordierite。因此Spinel之生成粗晶種多而細晶種少。此結果使Cordierite的生成溫度於1200oC由α-Al2O3、Enstatite、Mullite加上玻璃相SiO2直接合成（在不經Spinel步驟）。即α-Al2O3 + Enstatite + SiO2與Mullite + Enstatite + SiO2，直接生成Cordierite。其中以添加細晶種樣品C2-30 & C2-55最為明顯。上述的影響也隨晶種添加量越多而越明顯。
實驗中三種粒徑晶種之計算單層披覆量樣品（C2-15、C20-30及C40-55）皆可獲得最高之堇青石生成量。而過多與過少晶種都使堇青石生成量下降，其中以細粒徑晶種C2-15現象是最明顯。

In this study, raw materials talc (d50=6.4 μm), kaolinite (3.1 μm), and α-Al2O3 (253 nm) powders were weighted and mixed firstly with each other at a stoichiometric composition of cordierite. Assumed that the raw materials powders were forming agglomerates of stoichiometric cordierite composition, acting as the reaction units. The calculated reaction unit that composed of the raw materials powders of 1 talc particle, 10.88 kaolinite particles and 3672.55 α-Al2O3 particles then determined to be 10 μm. Furthermore, this research added cordierite powders acting as seeds with particle sizes (d50) of 2.5 (C2), 21.5 (C20), 44.3 μm (C40).The calculated mixing weight fractions of the three seed powders that will surround the 10 μm reaction units with single layer were 15, 30, 55 weight % (-15, -30, -55), respectively. Experiment was analyzed by DTA, XRD, XRF, SEM, PSD techniques.

It was found that α-Al2O3 delayed disappearance with the fine seed additions, indicating that the reaction route for α-Al2O3 to form spinel that transforms to cordierite, subsequently is altered. In case of coarse seeds added, α-Al2O3 + enstatite → spinel + SiO2 occurred, while the fine seeds was added, mullite + 3 enstatite + 5/2 SiO2 → 3/2 cordierite occurred. Similarly, mullite diminished early, indicating that the two reaction routes for mullite : mullite + 3 enstatite → 3 spinel + 5 SiO2 by coarse seed addition, while mullite + 3 enstatite + 5/2 SiO2 → 3/2 cordierite by fine seed addition. Therefore, the spinel formation of coarser seed was more than finer. The result showed that α-Al2O3, enstatite, mullite and SiO2 will directly form that of cordierite at temperature about 1200oC. And the seeding effect increases with higher amounts of seed additions, especially for samples with finer seeds addition C2-30 & C2-55.

Seed particles that can reach single layer surrounding to reaction units, samples C2-15, C20-30, C40-55 will result in a higher amount of cordierite formation. And the effect increases with the finer seed additions, especially C2-15. Either insufficient amounts of seed addition or over-use of them gave the reduction in cordierite formation.

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