Sheer kaftan button down tunic vintage

I have owned this since the late 90's. Black sheer button down kaftan tunic with earthy circle design. Excellent vintage condition. No rips, tears or stains. Wear it buttoned or unbuttoned. Measures 23 inches armpit to armpit. 40 inches in length. Buttons only go halfway down, they end at 20 inches. I am 5'4 and this falls mid calf on me.