Easy⏱ time20 min + days$ cost4
Baking-Soda Stalactites
Two cups, some string and washing soda grow mineral spikes like a cave — just sped up.
Start building ↓
Result first
The build
Step 01
Make solutions
Saturate two jars of hot water with soda.
Step 02
Bridge with string
Drape string between the jars over a plate.
Step 03
Let it wick
Solution travels along the string and drips.
Step 04
Watch it grow
Over days, mineral deposits form spikes.
Working Principle
Solution wicks up and along the string, then evaporates at the lowest point, leaving dissolved minerals behind that build downward.
The science behind it
A closer look
It models real stalactite formation by deposition: water carries minerals, evaporates, and the solid stays behind.
Take it further
Variables to test
- 1 Compare cotton vs wool string for speed.
- 2 Raise the room temperature — faster growth?
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