ND1.93 glass bead Composition BaO-SiO2-TiO2 GLASS Refractive Index 1.93±0.01 Specific Gravity 4.1±0.2 g/cm3 Color White Form: Fine spheres powder Size 75-90um;60-80um;50-70um 40-60um;25-40um;10-25um (can be provided by specific request) Roundness 95% Opacity 1% Brightness (Retro-Reflective Coefficient) 400-600 CPL for different type; The brightness of glass beads used in the reflective fabric meet the EN-471 standard.