It is green the star stone -Lapisalazuri Stern - S1.E8

Souseiseki, the fourth doll of the Rozen Maiden, is introduced. She lives with an old man, named Motoharu, who believes her to be his late son, Kazuki, which forces her to stay with him. Suiseiseki is traumatized by her twin sister's resolve to choose the Motoharu over her. Moreover, Suigintou soon intervenes.