ตอนที่ 11: รุริใช้การวิเคราะห์อัญมณีเพื่อแก้ปัญหาความสับสนในการเลือกวิชา

11

Ruri cannot decide which elective courses to take. Yoko makes "thin slates" and examines them in polarized light. Ruri applies the technique to her sapphires to learn about their formation. Returning to the field, she seeks bits of the crystals' original host rock. Testing with hydrochloric acid reveals calcite. More searching in correlation with the story of the old shrine yields many more sapphires and a plausible model of their history. With more confidence and clearer self-knowledge, Ruri chooses to study Earth science. (Source: Wikipedia)