Containing only 20-50 pieces, these puzzles are unexpectedly difficult because it is hard to tell the up-side of individual pieces from the down-side.
Puzzles may feature sculpting, whimsies or double fits, and exploit aspects of visual perception such as subjective figures, illusory borders and background/foreground switches.
They are most difficult if done sight unseen.
Small puzzles are hand crafted to a plan, but sometimes the plan can be modified to personalise the puzzle.
Small puzzles with non-interlocking pieces
Puzzles with non-interlocking pieces, also called push fit pieces, are more difficult than interlocking puzzles
Small puzzles with interlocking pieces