THE CLASP MARK OF JOSEPH SHOEMAKER, PHILADELPHIA, CIRCA 1790; THE BUTTON MARK OF ZACHARIAH BRIGDEN, BOSTON, MID-18TH CENTURY

The monogram R.C.B. on the necklace clasp is that of Rebecca Cornell Biddle (1782-1870), the daughter of Clement Biddle (1740-1814) of Philadelphia and Rebekah Cornell (d. 1831). Clement Biddle was a Revolutionary army officer and later first US Marshal for Pennsylvania. In 1808, Rebecca married Nathaniel Chapman, a noted Philadelphia physician.