19th Century French Art Nouveau 18K Gold and Diamond convertible Necklace/ Brooch Pendant

19th Century French Art Nouveau 18K Gold and Diamond Convertible Necklace/ Brooch accompanied with Independent Gemologist Report reflecting a value of $3500
8.7 grams approx all inclusive. Brooch weighs 5.3 grams. Marked 750

One 18k yellow gold and silver, lady's combination pendant/brooch from the Georgian period. Designed with a large pear shape, rose cut diamond collet set at the top and set within a 13 prong setting, there are an additional (5) five smaller irregular shape rose cuts set within the interior of the design. Another single rose cut diamond is set within a drop location at the bottom of the item. Accenting the diamonds is a silver top application that is accented with a milgrain border. A pin, joint & "C" style catch is secured on the back.
Also, the item is accented with an 18k yellow gold (non-original) snake style chain. This chain attaches to the body by way of conventional spring style closure on both sides of the item. The total diamond weight is approximately 1.25ct.
Pendant: 32.3mm H x 31.1mm W, Necklace 16" L approx
Condition Report: nice