Is Pyrex glass the answer to long-term data storage?

Microsoft has just announced a major breakthrough in its efforts to commercialize Project Silica, its effort to etch data onto glass as an archival medium: the company has succeeded in making the etching technique work with the type of glass used in oven doors.

Previously, the Silica Project used a special type of molten glass, sufficient for research work but not for widespread use of Silica technology. Now, Microsoft has made it work with borosilicate glass, the type of glass found in Pyrex containers.

Furthermore, the silica remains the same. The objective has always been to store data “permanently”, on a medium that does not degrade over time. Or almost, anyway: the stated goal is to store data for more than 10,000 years, and the company has already tested it by burning films like Superman in glass to preserve them. A similar test also archived music for future generations.

Otherwise, even “archive” storage media can suffer from degradation. “Bit rot” can occur in everything from hard drives to recorded media like DVD-ROMs and rewritable optical media. Microsoft first experimented with encoding data in DNA, then moved to Silica in 2019. The Silica project encodes data holographically in glass only 2mm thick, and still does – now the glass used is much more commercially available.

Although Microsoft said the research phase on Silica was complete, it did not indicate that production would begin. Microsoft said in a blog post that it would “consider the lessons learned” from what it discovered. Microsoft published its results in a new article in Nature.

Microsoft also added that it has made progress in writing data. Rather than using the polarization of the glass to encode data, Microsoft can now use what it calls “phase voxels,” using the phase change of the glass instead. Many more of these voxels can now be written in parallel, Microsoft added. If bias voxels are used instead, Microsoft said it has found a way to simplify the writing process to just a pair of pulses.

Finally, Microsoft said it applied machine learning to optimize symbol encodings and better identify how data might “age” in the glass.

Of course, our descendants 10,000 years from now will need to be able to actually read the data. Let’s hope the silica glass doesn’t end up as a 21st century archival Zip drive.