Necklace of sea pearls with a diameter of 3 to 7 mm

Cultured sea pearls, size 3 - 7 mm. Silver cap with Ag 925 / 1000 fineness. Total weight 13,80 g. Necklace with irregularly shaped cultured sea pearls with a diameter of 3 - 7 mm, strung with knots. Silver rectangular engraved clasp with pearl. Marked: Sterling, fineness, Czechoslovak hallmark for old goods oak leaf. Europe, first half of the last century. 49 cm long.