Antique Turquoise&White Metal& Turquoise Bar Brooch

Very nice brooch, the turquoise is surrounded by marcasites. Condition is good,there is a marcasite missing. The material is silver tested but not hallmarked hence I sell it as white metal. There is a but of brown onto the blue, but I think is part of the stone.

The clasp works fine, and the brooch measures approx 4.2x1.5cm.Thanks for looking:-)