"Great art picks up where nature ends".
Marc Chagall
Typically, abstraction is used in the arts as a synonym for abstract art in general. Strictly speaking, it refers to art unconcerned with the literal depiction of things from the visible world. It can, however, refer to an object or image which has been distilled from the real world, or indeed, another work of art. Artwork that reshapes the natural world for expressive purposes is called abstract; that which derives from, but does not imitate a recognizable subject is called nonobjective abstraction.
If you look around at things and objects which surround us actually we will be surprised, how many there are abstract works of art created by the nature! For example, look at the sky! But if you want to see unbelievable picture you should use a special phototelescope =))