Louis Booth Oval Sterling & Mixed Metal Brooch with Semi Precious Stones

Pictured is a Sterling and Mixed Metal Semi Precious Stone Brooch by Louis Booth. The brooch is 3" x 2". The center metal is sterling. Tested with acid and polishes up extremely shinny. The outside perimeter is a filigree carved and chased I believe brass medal with 4 bezel semiprecious stones. The stones test with gem tester to be amethyst, garnet, tanzanite and I believe the other stone is lapis. The brooch is 20.6 grams and is signed Louis Booth.