Beautiful studio glass buttons, chunky rounded square shape, with swirls of brown in pale green glass. Applied small metal plate and metal loop shank. Probably mid 20th century. No back mark. Two examples shown - both slightly different as these are hand made. Perfectly smooth, so what appears to be a crack is just how the pattern was formed. Price is per button.

Size 11/16” (1.7 cm) square or 13/16” (2.1 cm) diagonally