The primer has been stored for a while. It is very thick on the bottom; the material adheres to the stick while stirring. Is it any good?
As long as the primer isn't solidified and doesn't have a very bad smell it should still be good. The thickness is cause by evaporation of the solvent. This is easily fixed by mixing in more solvent. Use water for water based primers and paint thinner for oil based primer. To figure out the type of solvent look at the label on the can for thinning and clean-up instructions.