Copper Seed Safe can be purchased at This is essentially a paper thin sheet of copper. It claims to be:

  • Fireproof
  • Waterproof
  • Easy to use
  • Requires no special tools — write with a pencil or pen


This was easy but slightly annoying because I wasn’t sure how hard I needed to press down while writing on the copper sheet. My first few words were done at a fairly normal writing pressure while the rest were at high pressure to make the maximum indentation.

Heat Stress Test

What’s concerning here is you can see the top left edge appears to have melted a bit. The lightly imprinted words in the top left are nearly illegible with some slight data loss. The discoloration does not make it easier to read. Though I will note that reading the back side of the sheet of copper was a bit easier for some of the words.

Corrosion Stress Test

Not great. We can see more of the copper sheet is disintegrating while the legibility of the remaining words is getting worse. Partial data loss.

Crush Stress Test

No hydraulic press required.

Catastrophic failure.