15/16" the long way, about 13/16" the short way, rounded rectangles that glow and shine. We think they're resin or a combination of resin and shell. They're very smooth, sleek and light in weight; too light to be glass or stone, but they look like shell, glass, and/or polished stone. The hole on the back is about 1.5mm.  No two will exactly match; all are earth tones and of those has red tones; all glisten with iridescent golds and silvers.  

Age unknown. Condition perfect.  You'll get the exact three shown.. Exceptional. Japan.