Antique 'Au Firmament' Pendant/Locket

Dated to the late 18th to early 19th century, a very special blue 'Au Firmament', 'To the Heavens of Stars' pendant. It is rare to see the 'au firmament' piece in a pendant form. The pendant/locket has lovely scallop edges and diamond stars, and the original bale has two extra diamonds. It is set in 15k yellow gold. There are a few surface wear on the left side of the pendant when inspected at certain angle. Overall in good condition.  Size: Approximately 30mm NS x 18mm width (including the bale)