Mother of Pearl or Nacre is secreted by the epithelial cells of the mantle tissue of certain species of mollusc.

Small, hand-cut shapes with straight edges, called 'Tesserae', are typically laminated to either a marble, porcelain, ceramic or more recently a resin base. The tesserae are hand-placed and closely sandwiched together, creating a mosaic or pattern ( such as Basket-Weave ).