Fig. 3From: Micro-Raman spectral identification of manganese oxides black pigments in an archaeological context in Northern ChileMicro-Raman spectra. Raman spectra of different manganese oxides a Ta-1 (pyrolusite + manganite), b Ta-14 (pyrolusite), c Ari-26 (manganite) and d Ari-27 (manganite + cryptomelane). P* pyrolusite, M manganite, C cryptomelane, Q quartzBack to article page