A diamond and vari gem-set insect brooch

A diamond and vari gem-set insect brooch, naturalistically modelled with baroque pearl abdomen, octagonal step-cut sapphire thorax, old brilliant-cut diamond head and circular mixed-cut ruby eyes, his wings edged with further similarly cut rubies and rose-cut diamonds, two colour precious metal mounted, (one diamond deficient, pearl untested for origin, fitting later replaced), length 2.9cm
Condition report:
Chips, scuffs and surface-reaching fractures to the sapphire, rubies and diamonds. The sapphire and rubies contain areas of angular whiteish colour zoning and feather/fracture inclusions. Diamonds are mostly bright and lively but some stones have a greyish, fractured appearance. One diamond is missing. The pearl is untested for natural/cultured/freshwater origin and has scuffs, pits and blemishes to the nacre surface. The mount has surface wear, scuffs, nicks/chips and areas of porosity and some tarnishing. The porosity may be due to solder repairs. The brooch pin and visor clasp are currently functioning but the clasp may be later replaced. Metal standard is untested. Date of manufacture unknown. Gross weight approx. 6.4gm.