Vinage German unmarked porcelain black haired Doll

Russian vintage porcelain doll I found at a estate sale I am not sure if she came with this dress but it does look very clean they had it as a display behind a cabinet with glass doors so there is hardly any damage to this doll very clean I was told that the person that owned this doll had a collection of them and I was able to get a hold of this one very beautiful it does have some markings on the back of the shoulders but I cannot read what it says so please if you have experience with this dolls I don't know from what period of time she's from or maker but it's available for anybody that is interested about 12" long