Each bead is completely unique as the application method and dichroic achieve a different result in each bead. The size is approximately 14mm round with a base of transparent Aqua Chiarissima (pale Aqua) Moretti Glass wrapped in 24kt gold foil and then the dichroic is applied and then the entire bead is encased in clear Murano Glass. They are exquisite.
A dichroic filter or thin-film filter is a very accurate color filter used to selectively pass light of a small range of colors while reflecting other colors (from Wikipedia). Dichroic Beads are a great way to upscale your Murano Glass Jewelry.