This is a fascinating little piece. For sale by Romanov Russia of Chicago, they note that it is, ” An antique diamond brooch/pin with a guilloche enamel egg charm, Russian, circa 1900. Unmarked, attributed to Peter Carl Faberge. A beautiful lavender purple guilloche enamel egg with a silver cluster, hanging on a rose diamond encrusted chain held by a diamond set bar pin. The bar pin is set with a row of nine single cut diamonds and accented with two Old European diamonds at the ends. All diamonds are set in silver over rose gold. Approximate total diamond weight 1.8 ct. Width – 36 mm (1-3/8 in.) Height – 43 mm (1-5/8 in.).
It sells for USD$6,800.