Laser etched quartz or diamond. There was an article about it in the last few years but I cant find it. I'm pretty sure 10,000 years was the time mentioned. Fo

Laser etched quartz or diamond. There was an article about it in the last few years but I cant find it. I'm pretty sure 10,000 years was the time mentioned. Found it. It's glass not quartz or diamond and it's supposedly stable for 13.8 billion years https://www.southampton.ac.uk/news/2016/02/5d-d https://www.southampton.ac.uk/news/2016/02/5d-d