Bob Mackie Inspired Sequined Dress Unknown Designer/Brand

This is a GORGEOUS one of a kind dress. No tags to know brand, designer or size. However, dress fits like a size 8. Measurement are below. Happy to answer any questions! Pictures just do not do this dress justice for is beauty! Back zipper. Side slits on each side. Not one single flaw or loose thread or sequin missing. Immaculate condition. Shoulder to bottom hem 58.5 inches Arm pit to pit 19 inches Hips 21 inches Slits on both sides of dress. both are 30 inches from hem up.