Gorgeous piece! The quality of these moonstones is insane - Eight clean and clear 9x7mm stones with blue fire - set in a mid-century heavy 14k gold setting. From my research there are similar styles from Tiffany & Co and there is also an identical makers mark (what appears to be a triangle over two H's see image), which is also found on the same Tiffany pieces (see link below) so perhaps this is designer... An amazing piece through and through...
Same hallmark as seen on sold piece from Wilson's Antique Jewelry:
https://www.wilsonsestatejewelry.com/products/tiffany-co-retro-sapphire-moonstone-14-karat-gold-wreath-brooch-1?srsltid=AfmBOoqjc71CeX7qpECBKa1yWyyayNXZVUhJanr56S3Fg4OcU3iqZ6Ao
