Sputter deposition, also called physical vapor deposition (PVD) is a gas-based method of depositing ultra-thin films of a given material on a substrate surface. The end result is similar to electroplating, only sputtering creates layers with thicknesses so fine they’re often measured in angstroms, which are 0.1 nanometer. There were so many sputtering (or PVD) machines spread around the MMO site that I couldn’t hope to keep track of them. Some of these are employed immediately after the glass washing to nickel plate the substrate. According to WD, this increases the value of each platter by roughly 6x.