Thank you for your response, how very sad that this once great Russian family has died out completely. Princess Olga was a very striking and elegant woman, and was regarded by everyone as being very "smart', and had great presence.
I always thought it was strange that she was a lady in waiting to the Empress, as compared to the other ladies in the suite, who were quite frumpy and old fashioned, she was so different looking in many ways.
There is a famous portrait of her dressed all in black sitting in her drawing room, which shows how strikingly elegant she was. I cannot recall the artist.