Titanium Nitrate (TiN) is a FDA approved medical coating for in-body use. Titanium Nitrate is a hard coating that has a very strong bond to the magnet. TiN is resilient to most chemicals and environmentally friendly. This special coating works to protect from humidity and fluids. The finished color is a metallic gold with a smooth surface. Typically the thickness is around 2-3 microns. The maximum operating temp is approximately 500o C.