The Black Madonnas are in many European and other countries, see overall post here at Europe Road Ways, Black Madonnas. We thought we found one here, in Gdansk Cathedral, Poland.
I assumed it to be another wonderful Black Madonna, but there is no baby. Checking, and do follow the path at Bogomilia, A Site for the Unsung, Sara the Black, this does appear to be Sara the Black, so far.
Now to go back to other Black Madonnas to see which may also be the Gypsy Sara the Black. Start with Wikipedia on this - at ://en.wikipedia.org/wiki/Saint_Sarah . Find the stories. An Egyptian servant to Mary in Egypt? Other stories? Here is information about an annual pilgrimage of Roma in France, homage to a Sara the Black, see //www.geocities.com/~Patrin/stsm01.htm.
If you look at the crescent here, then at the symbol for Gitans at the website, that also includes a crescent, perhaps you know where to look to see if there is a connection. The crescent also can relate to early two-horned moon symbols, or Mithra's horns, from the bull overcome by Mithra - Mithraism being the dominant religion before Christianity (Mithra ascended after his death in about 200AD?) see //www.mysteriousbritain.co.uk/gods&goddesses/mithra.html. See also Bogomilia, A Site for the Unsung, Sara the Black, for more on Mithraism. Do not go to these places if you do not like finding roots.
Apparently the first historical reference dates to 1521, hand-written legends are located at Arles, and she has long been the patron of the Gypsies. There are many stories of her origins and works, including that she accompanied the Two Maries to the tomb and found it empty, and she also announced that event. Or, she was a black servant, and so many versions - go read.
The destination church for the annual May pilgrimage is Saintes-Maries de la Mer. This is a start. A new direction for us in understanding these wonderful paintings and sculptures.