20 photos of artwork painted entirely with coffee

Some people drink coffee, UK artist Maria A. Aristidou paints with it. 

"I use [watercolor painting] paper and around five different coffee blends," she wrote in a blog post about her art. 

With subjects ranging from Albert Einstein to Darth Vader, we've compiled some of the coolest works from Aristidou's Instagram in honor of National Coffee Day (Sept. 29).

Keep scrolling to learn more about the artist and her unique paintings.