Images via: (clockwise from top left) 
“Stacks” by studio tdes, “Pebble Stack” by Ian Griffiths, “Ceramic bowls” by ~My aim is true~, “coin stacks” by frankieleon, “stacked” by Magnus Hagdorn, “stacks” by Michael Cory, “Wine Corks_2813” by Barta IV, “tire stack” by Markus Spiske (all images cropped from original sizes)
