Grapefruit is oblate in shape, ranges in diameter from 3 to 5 inches and can weigh up to 150 g. Characteristically, it has thick, tough skin than that in the oranges. Inside, the fruit is segmented into arils as in other citrus fruits.
Nacre (/ËneÉªkÉr/ NAY-kÉr also /ËnÃ¦krÉ/ NAK-rÉ),[1] also known as mother of pearl, is an organic-inorganic composite material produced by some molluscs as an inner shell layer; it also makes up the outer coating of pearls. It is strong, resilient, and iridescent.
Nacre Is The Final Factor In Grading Pearls. Both of the grading systems described above focus primarily on the luster and surface quality of the pearl to determine its grade. But keep in mind that other factors also contribute to the quality and final grade of any pearl.