This is a Hard-To-Find, VINTAGE, Mid-Century "Gold Tone Modernist Open Ribbed Expanding Twisting Eternal Atomic Swirl Circle Pin Brooch" from the mid-1960s. My neighbor’s mother purchased this Pin in 1965 and wore it occasionally over the past 55 years. In EXCELLENT Condition, there is NO DAMAGE and it comes from a smoke-free, pet-free home. With a diameter of approximately 2 1/4th inches, the swivel pinback measures approximately 1 inch long and works smoothly, holding securely; this pin is NOT Marked. This BEAUTIFUL mid-century Brooch is a quintessential example of high-quality 1960s costume jewelry. Much nicer in person, the simplicity of the gold cutout spiral eternal atomic swirl is quite LOVELY. With an understated, modernist beauty, this Pin has an abstract quality and a flowing, bending appearance. ATTRACTIVE and well-made, it is quite DIMENSIONAL with a flattering shape and size. The twisting rings flare outward, creating a UNIQUE and ELEGANT Pin that is also SIMPLE and PRETTY. The open ribbed expanding circle design will add interest to what ever you wear it on; lapel, jacket, blazer, coat, sweater, blouse, shirt, vest or other pinable place. It is IDEAL for daily wear of special occasions!