Made of porcelain, not glass, and each piece has a hole in the center for threading. I believe that combining it with other materials will create luxurious items. Lucky patterns such as plants, animals, and auspicious designs are hand-painted and fired onto the pieces. I am selling 105 pieces together, and of course, shipping is free! ^_^ The dirt is just natural dust, so it will come right off if you wipe it with a damp cloth.