Diamonds cut from coloured mirror, measuring 24×15×3 mm. The silvering of the mirror contains no mercury and is safe to use in closed spaces. Although the back is sealed with epoxy paint, it is advised that a neutral glue (not thinset or mortar) is used, such as PVA or Collall. Due to the artisanal manufacturing process, actual items may not perfectly match the photos. Please remember that stained glass is more fragile than vitreous or sintered mosaic. Sharp edges - not suitable for use by children.