Gemmail describes a type of stained glass

Stained glass

The term stained glass can refer to coloured glass as a material or to works produced from it. Throughout its thousand-year history, the term has been applied almost exclusively to the windows of churches and other significant buildings...

 art developed during the 1930s by French painter Jean Crotti

Jean Crotti

Jean Crotti was a French painter.Crotti was born in Bulle, Fribourg, Switzerland. He first studied in Munich, Germany at the School of Decorative Arts, then at age 23 moved to Paris to study art at the Académie Julian. Initially he was influenced by Impressionism, then by Fauvism and Art Nouveau...

. It differs from traditional stained glass techniques in that the individual pieces of colored glass are not joined by lead came

Came

A came is a divider bar used between small pieces of glass to make a larger glazing panel, sometimes referred to as leaded glass. This process is then referred to as "leading". Cames are mostly made of soft metals such as lead, zinc, copper or brass. They generally have an H-shaped cross section,...

, but overlapped and glued together with a clear substance. Pablo Picasso

Pablo Picasso

Pablo Diego José Francisco de Paula Juan Nepomuceno María de los Remedios Cipriano de la Santísima Trinidad Ruiz y Picasso known as Pablo Ruiz Picasso was a Spanish expatriate painter, sculptor, printmaker, ceramicist, and stage designer, one of the greatest and most influential artists of the...

is said to have hailed gemmail as a new art form.