Read books about past and present artists who created lithographs such as "Great Lithographs" or "Miro Lithographs." Develop a foundation of knowledge on the process used to create lithographs. Learn the difference between fine art lithographs, which are never to be confused with offset lithograph reproductions. Peruse www.maserworksfineart.com to view fine art lithographs. Click on "full description and image" which gives close-up detail of an original lithograph.
Look for a signature. An artist creates a "master" image on a plate or stone. The artist, or a master printer under her supervision, will produce a print. The artist signs each impression as an approval if she considers it a good print. She signs her name in pencil along the lower right-hand corner of the paper, close to the bottom of the image. Toulouse-Lautrec used a signature monogram. On occasion, the master printer will place his mark or "chop" on the paper, usually a seal.
Check the series and edition numbers. Penciled underneath the signature are two numbers, which the artist places in the corner of the print like a fraction. An example of numbering on a lithograph edition is Jim Dine's "Double Apple Palette with Gingham" (see Resources) from 1965. The number 17 denotes what number print in the series. The 23 below tells how many impressions or total number of prints in the edition.
Look at the lithograph under magnification, if possible. Color on an original hand-pulled lithograph will be solid and rich. Images from offset lithography are composed of thousands of dots. Ink on a fine art lithograph is smooth and color lies flat on the printing surface. There might be a slight distinction from the texture of the stone or metal, which can create a random dot pattern. It will not have the precise dots found in newsprint or posters.
Regard the paper. A hand-pulled lithograph will be on heavyweight, acid free paper such as Japon, Arches script or block watermarked paper. It may be handmade or hand torn. Fine art lithographs lack signs of relief, such as the lack of a rim of ink, raised ink surface or markings from a metal plate. A certificate of authenticity accompanies the lithograph. It tells about the lithograph's background, processing method and number of prints in the edition.
Do careful research if you are considering purchasing an original fine art lithograph. Prominent lithographs are a deep investment. Note if the artist was directly involved in the production of the print. The more directly involved he was in the process, the higher value the print. Certify if the lithograph was mechanically reproduced or by hand. Discern who actually pulled the prints, the artist or the master printer who followed directions. Reproduction prints are not implemented by the artist or under his direction.