↩ 🔵 🔵 🔵 ❪✺❫ Electromagnetic Concepts ○ Spectroscopy 𓆩⚪𓆪 ❪✺❫ Spectral Fitting Concepts ○ ❪✺₁❫ Spectroscopic Classes ○ ❪✺₂❫ Spectroscopic Domains ○ ❪✺₄❫ Spectroscopic Sets ○ ❪✺_❫ Spectroscopic Subs ○ Color ○ Color Space ○꠹ Hardness ○