Six high-excitation PN are found to have gas-phase iron abundances less than solar by M.2 dex, and carbon abundances larger than solar by M3.8 dex. The objects have solar abundances of oxygen, and this supports the idea that the missing iron has condensed into grains. Efficient condensation of iron, and of all carbon not in CO molecules, is expected before the shell becomes ionized. The presence of some gas-phase iron therefore requires partial destruction of the grains.