Andrew Nethercott Antiques has dated this piece to the 1880s.
Polished finely figured specimen stones slotted together into a woven geometric plaid mosaic, laid onto a slate back and mounted into an unmarked tested silver oval frame with thick rope twist surround.

Strong hinged pin and hook.
Large enough to be used as a shawl or cloak pin.
All in excellent, sound, bright condition with no damage or repair.
Width 2,15/16" x 2,1/16" or 74mm x 53mm
Weight 55 grams.
A good quality piece ready to wear or collect.
Andrew Nethercott Antiques has dated this piece to the 1880s.
Works of art, collectables, scientific and decorative antiques from the 17th - 20th century
You can view the stock and full dealer information on the Andrew Nethercott Antiques Profile Page