Beautifully Framed Miniature Botanical Painting Columbine Lincoln Fine shop Arts Shop

A sweet miniature painting of a Columbine. It is hard to tell if this is a watercolor painting, gouache, or even oil on paper. There is a signature, I think it reads Nash but not sure, it is so small and hard to photograph shop through the glass. Columbine is handwritten on the mat to which the painting is mounted. It is very old, possibly in the range of 1920s to 1940s. Triple matted and framed in wood. It once had a brass ring on top but the ring is missing. On the back is a label that reads Lincoln Fine Arts Shop.

Measures 7 5/8" tall, 5 1/8" wide , and the painting itself is 4 1/4" x 2"