Your all boringly conventional. I've seen this photo before. It's actually a grain of sand sat on a microscopic field of tiny grass shoots, shot with a Humongous macro lens. Easy how some people are fooled.
A boulder. In geology, a boulder is a rock fragment with size greater than 25.6 centimetres (10.1 in) in diameter. Smaller pieces are called cobbles and pebbles. While a boulder may be small enough to move or roll manually, others are extremely massive.
So is Uluru (Ayers "Rock") really a boulder? You can't roll it. Won't budge. Its a bloody big fragment..