Spectrum Mass abs. coef. (cm2/g) of amorphous silicate grains Mg$_{(1-x)}$Fe$_x$SiO$_3$, x=0.1, processed sample, T = 300 K Spectrum Mass abs. coef. (cm2/g) of amorphous silicate grains Mg$_{(1-x)}$Fe$_x$SiO$_3$, x=0.1, processed sample, T = 200 K Spectrum Mass abs. coef. (cm2/g) of amorphous silicate grains Mg$_{(1-x)}$Fe$_x$SiO$_3$, x=0.1, processed sample, T = 100 K Spectrum Mass abs. coef. (cm2/g) of amorphous silicate grains Mg$_{(1-x)}$Fe$_x$SiO$_3$, x=0.1, processed sample, T = 30 K Spectrum Mass abs. coef. (cm2/g) of amorphous silicate grains Mg$_{(1-x)}$Fe$_x$SiO$_3$, x=0.1, processed sample, T = 10 K

Spectrum Mass abs. coef. (cm2/g) of amorphous silicate grains Mg$_{(1-x)}$Fe$_x$SiO$_3$, x=0.2, processed sample, T = 300 K Spectrum Mass abs. coef. (cm2/g) of amorphous silicate grains Mg$_{(1-x)}$Fe$_x$SiO$_3$, x=0.2, processed sample, T = 200 K Spectrum Mass abs. coef. (cm2/g) of amorphous silicate grains Mg$_{(1-x)}$Fe$_x$SiO$_3$, x=0.2, processed sample, T = 100 K Spectrum Mass abs. coef. (cm2/g) of amorphous silicate grains Mg$_{(1-x)}$Fe$_x$SiO$_3$, x=0.2, processed sample, T = 30 K Spectrum Mass abs. coef. (cm2/g) of amorphous silicate grains Mg$_{(1-x)}$Fe$_x$SiO$_3$, x=0.2, processed sample, T = 10 K

Spectrum Mass abs. coef. (cm2/g) of amorphous silicate grains Mg$_{(1-x)}$Fe$_x$SiO$_3$, x=0.4, processed sample, T = 300 K Spectrum Mass abs. coef. (cm2/g) of amorphous silicate grains Mg$_{(1-x)}$Fe$_x$SiO$_3$, x=0.4, processed sample, T = 200 K Spectrum Mass abs. coef. (cm2/g) of amorphous silicate grains Mg$_{(1-x)}$Fe$_x$SiO$_3$, x=0.4, processed sample, T = 100 K Spectrum Mass abs. coef. (cm2/g) of amorphous silicate grains Mg$_{(1-x)}$Fe$_x$SiO$_3$, x=0.4, processed sample, T = 30 K Spectrum Mass abs. coef. (cm2/g) of amorphous silicate grains Mg$_{(1-x)}$Fe$_x$SiO$_3$, x=0.4, processed sample, T = 10 K