Microsoft is continuing to develop a glass storage technology aimed at preserving large volumes of information for extremely long periods. The initiative, known as Project Silica, explores how data can be written into glass rather than stored on conventional media such as hard drives or magnetic tape, with the goal of creating a far more durable archive format.

The project was first introduced in 2017 and initially relied on high purity fused silica. Microsoft has since shifted to borosilicate glass, which is less expensive and more readily available, a change that could improve the economics of the technology if it moves closer to wider use.

Data is written into the glass using femtosecond lasers, which create tiny three dimensional structures known as voxels inside the material. Microsoft has also simplified the readout process: where several microscope cameras were previously needed, the company now says a single camera is enough to capture the encoded data for decoding and recovery.

According to the reported figures, a glass plate measuring 12 by 12 centimeters and just 2 millimeters thick can hold around 4.84 terabytes of data distributed across 300 internal layers. The technology is designed for archive use rather than fast everyday storage, but Microsoft says the material could remain readable for more than 10,000 years, even under severe thermal stress tests.

Project Silica is therefore being positioned not as a replacement for SSDs or HDDs, but as a solution for information that must survive for generations, such as cultural records, scientific data, and long term cloud archives.