The bug brooch does not have a metal mark but was tested with nitric acid and a "kee" tester to be 14k solid yellow gold. It weighs 12.6 grams. From North to South the body measures 1 1/8" . The wing spand measures 1 7/8". Set in the body is a black opal doublet. It measures 15 mm x 10 mm which makes it approx 4.10 cts. The piece is in nice condition.