SortStack #3640 — 2036-05-27

By weight · Order from lightest to heaviest.

1. A modern US penny 2.5 g

   Pennies have been mostly zinc since 1982 — only the thin outer coating is actually copper.

2. A one-euro coin 7.5 g

   Its two-metal design is not just style — the distinct layers give vending machines an electromagnetic signature to verify.

3. A house sparrow 28 g

   House sparrows have followed humans to every continent except Antarctica — one pair even nested deep inside an English coal mine.

4. A liter of water 1 kg

   The kilogram was originally defined in the 1790s as the mass of exactly this much water — the tie was only fully broken in 2019.

5. An adult male giraffe 1.2 t

   A giraffe's heart generates about double the blood pressure of most mammals to push blood two meters up its neck to the brain.

6. The Great Pyramid of Giza 5.8M t

   Roughly 2.3 million stone blocks were stacked over about 20 years — averaging a block placed every few minutes of every workday.

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