ARNANO, a French company specialising in microelectronic technology, has created a perennial support for microscopic engraving technologies. Microscopic engraving is a technology used for archiving purposes due to the longevity of its results. The method is executed on ultra-resistant wafers made of synthetic sapphire. The wafers are often no more than 200 mm in diameter with a resolution of 20 nanometers. All types of information can be recorded on this extremely durable support. Synthetic sapphire can resist fire and acid, and remain intact for several millenniums. The technology used to produce the disks is called Mineral Thermolithography. It is based on the thermal exposure of a thin reactive metal film. After the surface preparation, the metal film is fixed on the sapphire disk. Following this, the information is engraved on the wafer with a laser, and the exposed areas removed. The production costs around 5000 euros per disk. Arnano uses the same technology to create dials for luxury watches, their principal source of income.