Experts recommend that the purchase of crystal glass tableware can be made by voice, feel, appearance, etc. on ordinary glass, leaded crystal glass, lead-free crystal glass difference. Ordinary Glass Products Color Dim, refractive index is poor, rough workmanship, feel poor, and even some places have bubbles, gently percussion sound boring. Crystal Glass products relative to ordinary glass products luster bright, refractive index strong, exquisite workmanship, feel good, look like crystal made, gently tap the crisp metal sound. Leaded Crystal glass products and lead-free crystal glass products, compared to a slightly thicker.