Natural pearl and diamond brooch, Bolin, circa 1900. Photo Sotheby's.
Of organic design, set with a baroque-shaped natural pearl and single-cut and rose diamonds, Russian assay marks, case by Bolin. Estimation 55,000 — 65,000 CHF
Accompanied by SSEF report no. 73567, stating that the pearl was found to be natural, saltwater, with no indications of artificial colour modification.
Cf: Christian Bolin and Pavel Bulatov (ed.), Bolin in Russia. Court Jeweller, Moscow, 2001, pg. 159, no. 85, for a brooch of similar design by Bolin.
Sotheby's. Magnificent Jewels and Noble Jewels, Genève, 13 mai 2014 - http://www.sothebys.com/