I have enclosed a picture of the work. It measures about 8" X 10" sight size. I thought this might be a litho but when I took it out of the frame some of it rubbed of on a piece of paper making me think this is not a litho. Can you shed some light on the subject?
Picasso worked in multiple mediums and a great site to check out if your interested is here: http://www.masterworksfineart.com/inventory/picasso
. In looking at the picture I cannot make out the medium, which is difficult to do from a photograph anyway, but the work is titled
"TÍte de Faune Gris" which is part of a series of studies Picasso did for his famous "War and Peace" mural: http://www.tate.org.uk/whats-on/tate-liverpool/exhibition/picasso-peace-and-free
. The original is currently located in the Tate Modern Museum in London.
However studies can be done multiple times and there is nothing I can find that points to reproductions being made of the work so I would contact any of the two people I listed below as they are the experts on Picasso and can tell you what you have. I am not sure what they require in regards to materials for authentication, but they are the best ones to give you the answers to the questions you seek. Best of luck. Andrew Evans
T: +33 (0)1 47 03 69 70
Diana Widmaier Picasso | DWP Editions
T:+33 (0) 1 44 86 05 05