Clay works well. The Rosicrucian museum in San Jose has a cuneiform tax receipt stating that a goat was eaten by wolves, and therefore no tax is due on it.

This is similar, from 1634BC, but I don’t know what it says:

https://archive.org/details/mma_cuneiform_tablet_impressed_w...

They say M-Discs are analogous to carving data onto stone. I have my doubts though. Searched the web and found posts claiming they are just regular Blu-ray discs now.