Harvard researchers' dye method holds promise for long-term data storage

https://news.harvard.edu/gazette/story/2021/10/harvard-researchers-use-dyes-to-store-data/

"mixtures of seven commercially available fluorescent dyes... are dropped by an inkjet printer and read with a microscope that can detect the different wavelengths of light each dye emits... then decode the binary message in the molecules back to documents, books, photos, videos, or anything else that can be digitally stored. Theoretically, the data can be saved for a very long time — thousands of years or more... can be read with 99.6 percent accuracy... relatively cheap"

Related: Storing data for thousands of years | Microsoft Project Silica

https://www.youtube.com/watch?v=-rfEYd4NGQg