Vintage Celtic mizpah brooch (amethyst glass stone)

This little brooch, about 1-3/8" in diameter, has lots to tell us. The thisle, here adorned with an amethyst colour glass stone, is a traditional Scottish symbol. The brooch is signed Mizpah on the back, which is a Hebrew term that I understand means something like "may God watch over you". Mizpah jewelry, like sweetheart pieces, was often given to a loved one to suggest the strength of a bond, particularly in the event of a forthcoming separation. The brooch also has the symbol of a double heart with an arrow. I understand that these combined marks were used by Ward Brothers of the U.K. and by Miracle Jewelry, which took over Ward's designs in the 70s. The brooch is in great shape. I have listed another mizpah brooch separately.