Green Stone Sterling Silver Necklace Huge Statement

Lovely artisan made chunky green stone necklace with five large round faceted stones, sold to me as Chrome Diopside. Chrome Diopside commonly possesses a bubble type of inclusion which I do see in these stones but I believe these are glass stones. The four prong settings have a bezel just under the girdle of the stone. The setting, links and chain are made of .925 sterling silver. ‘S’ hook clasp closure. Hallmarked '925'. Necklace Length 20-Inch Stones are 20 mm