Figure 7From: Raman and SEM analysis of a biocolonised hot spring travertine terrace in Svalbard, NorwayRepresentative Raman spectra of carotenoids found in the layers. (a) beta-carotene, (b) astaxanthin, (c) zeaxanthin/lutein, recorded at 514 nm laser wavelength. The carotene detection is easier with the 514 nm laser wavelength because of the resonance effect.Back to article page