Vintage Sterling silver marcasite star pin brooch

This is a vintage pre owned brooch pin in excellent condition showing only a few signs of gentle use. M Genuine marcasite gemstones set in authentic 925 sterling silver in an open star design. About the size of a quarter and weighs 3.69 grams. Everything is in working order. No damage or missing stones noted. Not sure of era but guessing pre 90s. 925A Reasonable offers considered