Picture of Madame Petolas

Very beautiful picture of young woman. On the pack of the picture is the name of Madame Petolas written in pencil and the word is(coloriel). Probably means they added colour to the picture at the time.
At the bottom , right hand side of picture is signed Harris Ewing.
I looked him up, many photographers by that name, which one is he? And who is this mysterious woman, what did she do in life, would appreciate to know more.
Was she someone important??? An actress, singer????of the time.The colours are not faded, we guess, that picture was tucked in a drawer or something , looks brand new but it is very old! Not cracked, torn, a beauty!