Vintage 1960's Julius Lonschein maxi hostess dress

Vintage Diana Dean by Julius Lonschein 1960s hostess dress or mumu. Turquoise, coral pink and green. The fabric is beautiful but there are no tags to say what kind of fabric it is. I hand washed it and it washed beautifully. Ironed with a warm iron. No size tags but I am a size 4 and it fit me. It has an unusual way to get into it. The back wraps over to the front. Easy after you figure it out. Front pit to pit is 21 inches. Sleeves is 17 inches. Center back to hem is 53 inches.