A thermal barrier coating and deposition process for a component intended for use in a hostile thermal environment, such as the turbine, combustor and augmentor components of a gas turbine engine. The TBC has a first coating portion on at least a first surface portion of the component. The first coating portion is formed of a ceramic material to have at least an inner region, at least an outer region overlying the inner region, and a columnar microstructure whereby the inner and outer regions comprise columns of the ceramic material. The columns of the inner region are more closely spaced than the columns of the outer region so that the inner region of the first coating portion is denser than the outer region of the first coating portion, wherein the higher density of the inner region promotes the impact resistance of the first coating portion.