Portuguese-based artist Samuel Silva draws incredibly detailed, photo-realistic pictures using ballpoint pens.
This tiger portrait took him around 50 hours to complete with everyday black and coloured-ink pens.
And he drew this Afghan girl over 120 hours.
"It takes me forever to do my works," he told BuzzFeed in an interview. "The only thing that makes me keep going is my love for what I do and the ambition to go further and further."
Amazingly, Silva didn't actually study art. He graduated from law school in 2007, and describes himself as "a self-taught patient hobbyist".
“At the age of two I drew a recognisable butterfly hovering over a flower," he said. "My mother thought it was my father's drawing."
"In school I started developing my own style of ballpoint pen drawing in the back of my exercise books."
"Ballpoint pens are as underestimated as they are a powerful medium. I like them because they're challenging and hard to use."
"But they are not the medium I am most proficient with - they are just my latest experiment."
Samuel Silva's creations are also available as prints from DeviantArt.
