Answer: Glass fibre insulation

What you're looking at

Glass fibre insulation is a common material found in walls, attics, and around pipes in most buildings. It's made from spun glass and comes in batts, rolls, or loose-fill form. Workers install it to reduce heat loss and keep homes warm in winter and cool in summer. It's one of the most cost-effective insulation materials available today.

When photographed under extreme magnification, glass fibre insulation reveals a wild landscape of thin, delicate strands woven together with countless tiny air gaps. The individual fibres look almost like spun sugar or intricate spider webs, and the texture appears so organised and geometric that it looks nothing like the fluffy pink or yellow material you'd recognise in a loft space.

Search for repeating geometric patterns and extremely fine, hair-like structures when trying to identify fibrous insulation materials.

How players did

3 players made 4 guesses. It took 3 guesses before someone got it right.