Nanostructured Glass Could Provide Highly Durable, Deeply Dense Data Storage (phys.org)
Namarrgon writes: Using nanostructured glass, scientists from the University of Southampton's Optoelectronics Research Centre (ORC) have developed the recording and retrieval processes of five dimensional (position, size, and orientation) digital data by femtosecond laser writing. The storage allows unprecedented properties including 360 TB/disc data capacity, thermal stability up to 1,000ÂC and virtually unlimited lifetime at room temperature (13.8 billion years at 190ÂC) opening a new era of eternal data archiving.
Glass is hundreds of times more scratch resistant than the extremely delicate magnetic media they install in hard drives (ok it really isn't, but the sensitivity is just as crazy because of the nano-meter tolerances required). Of course, this technology could be used in a protective case, like a hard drive, especially if the density/aging rates are as stated.
Archiving suggests write-only, but this paper shows that the technology can be used for rewritable storage as well.
Why would anyone engrave "Elbereth"?
You underestimate archaeologists.
Hang on, there seems to be something embedded in the glass. Let's point a microscope at it.
The Long Now foundation has found a nice solution to this. Put some writing around the edge of the glass disc. Make the initial few words large enough to be readable without magnification, and then make the text progressively smaller to encourage people to grab a magnifier.