I don't think "Our Lady of Częstochowa" was painted black. I think you will find it is smoke damage.
Well, you are entitled to think whatever you want, but your thinking is taken out of blue sky, not supported by any shred of evidence. I'll start with questioning you: which copy of "Our Lady of Częstochowa" do you have in mind?
Do you mean the original replica, painted by Bolesław Rutkowski, brought from Poland in 1955 and placed in the first "barn" chapel in Doylestown?
Or the one copied by Leonard Torwirt, blessed by Pope John XXIII on Feb. 10, 1962 - and set in the main nave of the church, as a part of a bas-relief depicting the Holy Trinity?
Or maybe the copy inside the replica of the chapel found at the Jasna Góra Shrine in Poland - blessed and signed in Rome by Pope John Paul II in 1980?
The fact is - The REAL Black Madonna of Częstochowa in Poland got her fame and adoration MOSTLY because of her blackness and the scars on her right cheek. And of course because of the various legends - like the one about her miraculous defense of "Jasna Góra" Monastery against Swedes in 17th century.
Whoever decided to transplant the copies of the icon of Mother of God from Częstochowa onto the American soil must have made the conscious decision to import the BLACK icons, not the white ones. They are REPLICAS - meaning similar or identical copies of the original, preserving feature by feature, almost exactly as they are; small variations are acceptable but the major features must be conceptually preserved. In this case - one must paint her face black - or at least dark, but definitely not snow white. And one must keep the scars - exactly as in the original. Well, actually the Torwirt's copy is done in
slightly brighter tones than the original. Her robe might also vary - and this is because the original Black Madonna is often being adorned with various robes made of jewelry. There are eight known dresses for the image of Our Lady of Czestochowa. Currently the icon is clothed in the latest amber-diamond robe.
Leonard Torwirt, the author of the second replica for Doylestown, painted altogether 15 replicas of Black Madonna and they are all dark. Why would he ever made an exception for the one in Doylestown?
Bolesław Rutkowski, the author of the first replica for Doylestown, also painted many copies of Our Lady of Częstochowa - all black faced. Here is the one from the church in Podlesie Parish in Katowice: podlesie.net/~parafia/k_kosciol0.html.
The chronicles "The American Czestochowa past", by Father Michael M. Zembrzuski, record the story of the first image of Our Lady of Czestochowa in Doylestown:
The image of Our Lady of Czestochowa - placed in the first chapel in Doylestown, came to America from Czestochowa shortly before the chapel dedication on June 26, 1955. It was painted by a famous painter from Czestochowa, Boleslaw Rutkowski. At the request of Father Michał, the Prior of 'Jasna Góra' Monastery in Częstochowa Father Jerzy Tomziński commissioned the painting with Professor Rutkowski already in 1954, as soon as land for the first monastery in America was purchased.
Translated from: rozancowe-karty.com.pl/modlitwa/matka_boza_czestochowska_10.htm
Farther Zembrzuski exaggerates a bit - B. Rutkowski was not that "famous" but he was well known for his religious paintings, in Częstochowa, across Poland and abroad.
Boleslaw Rutkowski was born in Czestochowa in 1882. He initially studied drawing in Warsaw under Wojciech Gerson and Adam Badowski, then in Czestochowa under Pantaleon Szyndler working at that time at Jasna Góra monastery. Author of many religious paintings - commissioned for churches in Częstochowa and in other cities in Poland and abroad. Most of his work - apart from works preserved in churches - were destroyed or dispersed after his death in 1972. Located in the Museum of Częstochowa "Portrait of the Old Jew" and "Winter Landscape" testify to his outstanding painting skills and a great sense of color.
Translated from: poswiatowska.muzeumczestochowa.pl/2007.pdf
Image of Our Lady of Czestochowa is receiving public tribute in the main altar of the Shrine, in the convent chapel, the cemetery chapel and St. Anna Chapel. This icon, painted in Poland, has been personally blessed and signed in Rome by Pope John Paul II in 1980. Brought to American Czestochowa, it receives special honor here.
translated from: rozancowe-karty.com.pl/modlitwa/matka_boza_czestochowska_10.htm
The American version of Black Madonna image is done in slightly brighter tones than the original. The American copy was painted by Leonard Torwirt (*) in Poland and was blessed by Pope John XXIII on Feb. 10, 1962. Before being enshrined in the new Shrine in Doylestown, the painting traveled to US Polish parishes throughout the country for 4 years.
* Torwirt, not Toweitt as erroneously shown in the source of this quote
polishsite.us/index.php/emigration-and-genealogy/polonia-in-usa/364-american-czestochowa-in-doylestown.html?fontstyle=f-larger
Leonard Torwirt (1912-1967) became famous as an excellent copyist of Our Lady of Czestochowa. In 1957, at the request of Cardinal Wyszynski, he made two replicas of the miraculous image - one dedicated to Pope Pius XII and the second - the so-called "Picture of the Visitation", which - in the same year, despite the objections of communist authorities - began the pilgrimage of Polish parishes in the spiritual preparation of the Polish Church for the Jubilee of the Millennium of Polish Christianity, 1966.
translated from:
/pl.wikipedia.org/wiki/Leonard_Torwirt
B. Rutkowski's replica of Our Lady of Czêstochowa in Podlesie parish, Katowice, renovated
Leonard Trowirt's copy of the image of Our Lady of Czestochowa - on pilgrimage since 1957
The original Black Madonna, Czêstochowa, Poland
Icon of Madonna in Chapel of Our Lady of Czestochowa, Doleystown