LONDON.- The most searched for women artists on Barnebys, the world’s largest art auction search engine are Louise Bourgeois (best known for her monumental sculptures) and Cindy Sherman (photographer and film director, best known for her conceptual portraits).

The Barnebys database has 1.5m visitors a month to its 1,600 affiliated auction houses providing an invaluable research tool for art market trends. The company’s research programme aims to provide reliable art market data. It is able to track global and national trends in a huge variety of collecting categories.

This database shows clearly that a revolution that has taken centuries to arrive is underway in the art market and is sending prices for the work of women artists rocketing.

For centuries women have been the muses of many a great artist but few have been acknowledged as artists themselves. In the last few years all of that has changed.

Picasso , Monet , van Gogh , da Vinci , Rembrandt , Dürer and Dalí - one might think that art is a totally male domain and as artists women remained marginalised until the early 19th century. But thanks to the opening of art schools, the assertion of egalitarianism and the emergence of an art market, women artists are finally beginning to achieve the recognition they deserve.

Barnebys, the world’s fastest growing fine art auction search engine, has put together a list of women who played a key role in the changing history of art. At any given time Barnebys features over a half million items for sale through 1,600 auction houses worldwide and it is fast closing in on the 1.5 million visitors a month mark. Its aim is to put all auctions in one place for ease of access.

The sale of Georgia O'Keeffe’s painting Jimson Weed / White Flower No. 1 for $44.4 million at Sotheby's in 2014, set a new world record for a work by a female artist and sent a clear message to the world that female art had arrived - really big money was finally being paid for work by a women artists.

The O’Keefe result doubled the previous highest record for a work by a woman artist. Her record has stood since then, making O'Keeffe the unchallenged number one on the list of the most expensive female artists at auction. O'Keeffe is primarily known for her paintings of flowers and plants. She first attracted international attention in 1928, when six of her flower paintings sold for $25,000.

When Christie's held an auction of post-war art and contemporary art in the spring of 2013, they sold an untitled work by Joan Mitchell for over $11.9 million. Mitchell was one of the few successful women in Expressionism and her works were often abstract landscapes.

Another female artist in the Million Dollar Club is Berthe Morisot who was active in the second half of the 1800s, a contemporary of artists such as Edouard Manet, Pierre-Auguste Renoir and Edgar Degas and she was married to Edouard Manet's brother, the artist Eugène Manet.

When Berthe Morisot's portrait of a doe-eyed woman, ‘After Lunch’ sold for $10.9 million, it helped power a wave of interest among collectors and dealers looking to identify undervalued female artists. A woman's signature in the bottom corner of a painting had long spelled a bargain. Male artists in the same artistic school or period can fetch more than ten times the price of a woman's best work.

While the debate continues over whether talent, sexism or lack of promotion has held women artists back, it’s a fact that prices and recognition for female artists have always lagged behind those of their male counterparts. That is now changing and the following woman artists have had a role in this sea-change.