Spectrum Vis-NIR reflectance spectrum of Huy pigment (PIG_0172_A_608), powder with grains < 50 µm Spectrum Vis-NIR reflectance spectrum of Huy pigment (PIG_0172_A_601), powder with grains < 160 µm, d=1.01 g/cm3 Spectrum Vis-NIR reflectance spectrum of Huy pigment (PIG_0172_A_607), powder with grains 100-200 µm Spectrum Vis-NIR reflectance spectrum of Huy pigment (PIG_0172_A_606), powder with grains 200-400 µm Spectrum Vis-NIR reflectance spectrum of Huy pigment (PIG_0172_A_605), powder with grains > 400 µm

Spectrum Vis-NIR reflectance spectrum of Huy pigment (PIG_0172_A_601), powder with grains < 160 µm, d=1.37 g/cm3 Spectrum Vis-NIR reflectance spectrum of Huy pigment (PIG_0172_A_601), powder with grains < 160 µm, d=0.95 g/cm3 Spectrum Vis-NIR reflectance spectrum of Huy pigment (PIG_0172_A_601), powder with grains < 160 µm, d=1.55 g/cm3 Spectrum Vis-NIR reflectance spectrum of Huy pigment (PIG_0172_A_601), powder with grains < 160 µm, d=1.93 g/cm3

Spectrum Vis-NIR reflectance spectrum of Huy pigment (PIG_0172_A_101), raw block #1, face #1 Spectrum Vis-NIR reflectance spectrum of Huy pigment (PIG_0172_A_301), block #2, sawn face #1 Spectrum Vis-NIR reflectance spectrum of Huy pigment (PIG_0172_A_301), block #2, raw face #2

Spectrum Vis-NIR reflectance spectrum of polished slice #1 of Huy pigment (PIG_0172_A_401), spot #1

Spectrum Vis-NIR reflectance spectrum of Huy pigment (PIG_0172_A_903) painted on limestone block Spectrum Vis-NIR reflectance spectrum of limestone block