Features of the face of Buddha statues: 

1) Hairstyle: The head is tightly covered with small spiral shapes of hair. This is called “Rahatsu”.  On the top of the Rahatsu hair is a round bun. This is called “Nikkei”. It stores the wisdom of Buddha Amida. The front of the Nikkei is adorned with a small red or transparent ball. This is called “Nikkeisyu,” representing the light of wisdom. 

2) Forehead:  In the center of the forehead is a mole-like feature made of one long white hair in a rounded shape. It gives off light to the world and is called “Byakugo.”  

3) Neck: There are three wrinkles on the neck called “Sando,” which, according to one theory, represent three steps to enlightenment. 

4) Eyes: The face of Buddha statues is mostly expressionless, with the eyes half-open. This style is called “Hangan” and represents a meditative state, with the mind deeply calm.

Four Ranks of Buddha Statues

The world of Buddhist statues has its own ranking system. At the top is Nyorai, the figure of Buddha at the stage of enlightenment. There are also other Nyorai. Next is Bosatsu, who is on the path to becoming Nyorai. Every Bosatsu dedicates all their efforts to saving people. The third rank is Myo-o, characterized by an angry face. They scold people to lead them on the right path. The last rank is Ten. They are guardian gods in the Buddhist world. They were originally gods of ancient Brahmanism or Hinduism.

●飛鳥時代輪郭は面長で上下のまぶたがアーモンド型をした涼しげな目と高い鼻、口元は笑みを浮かべ異国の雰囲気。 

●奈良時代目は細部のラインまでしっかりと口元は力強く表現。より人間に近い写実的で自由な造形。 

●平安時代デフォルメされたおもしろい顔つき。目はほぼ平行に、口はふっくら貴族らしいやわらかな顔のパーツも多い。 

●鎌倉時代目には玉眼(ぎょくがん)という水晶が埋め込まれ、リアルな人間に近い力強い表現。
Asuka period: Elongated face outline, almond-shaped cool eyes with upper and lower eyelids, high nose, mouth with a gentle smile, giving a foreign impression.  
Nara period: Eyes expressed with detailed lines, mouth depicted with strength; more realistic, naturalistic, and free in form.  
Heian period: Faces with stylized, almost caricature-like features; eyes nearly horizontal, mouth plump, with soft and refined features typical of aristocrats.   
Kamakura period: Eyes inlaid with crystal spheres (gyokugan), producing a powerful expression close to real human likeness.
筆者作成
印相

●施無畏印(せむいいいん)……大丈夫!安心してね。
●与願印(よがんいん)……あなたの願いをかなえましょう。
●説法印(せっぽういん)……説法をしますよ。聞いてね。
●合掌印(がっしょういん)……左手が人間で右手が仏さま。合わせて仏を目指す。
●刀印(とういん)……邪悪なものを断ち切る。
●智拳印(ちけんいん)……最高の悟り。絶対的世界。
●定印(じょういん)……瞑想に入るときの手
Mudrā (Hand Gestures / Seals of the Buddha)
施無畏印 (Semui-in): “Don’t worry, be at ease.”     
与願印 (Yogan-in): “I will grant your wish.”  
説法印 (Seppō-in): “I am preaching the Dharma, listen.”    
合掌印 (Gasshō-in): Left hand = humans, right hand = Buddha; together aim toward Buddhahood.   
刀印 (Tō-in): “Cut off evil.”   
智拳印 (Chiken-in): Symbol of supreme enlightenment and ultimate truth.   
定印 (Jō-in): Gesture for meditation.

外部リンク https://kinarino.jp/cat7/42974