he painting is an art print titled "Serenity" by the artist Mary G. Gricki, created in the 1980s. 
Details
Artist: Mary G. Gricki.
Title: "Serenity".
Medium: It is a lithographed art print, often created with a protective textured finish to give it the appearance and feel of a canvas painting.
Subject: The artwork depicts two white or light-colored horses running in a field, kicking up dust around their legs.
Availability: Prints of this artwork were widely available and sold through various art print suppliers and retailers. 
Size
Picure 5x7
Frame 10.5x9