During George Washington's presidency, Martha Washington purchased readily available pearl jewelry that was imported or made by Philadelphia and New York jewelers. Examples of Lady Washington's pearl jewelry are part of the Mount Vernon Collection. Add a touch of classic elegance to your jewelry collection with these genuine freshwater pearls. The white cultured pearls on the 48" necklace measure 8-9 mm in diameter. This extra-long strand is easy to style doubled, tied, knotted or loose and long.