Decatur is a small city located in northeastern Georgia, just 5 miles northeast of Atlanta. The city was founded in 1823 at the intersection of two Native American trails and named after US naval hero Stephen Decatur.
The main function of a head gasket is to hold engine compression while keeping oil and coolant circulation separate. Undetected blown head gaskets cause coolant and oil mixing, which could lead to severe engine damage, such as engine block cracking.
There's no way to tell that a cylinder head is cracked without actually taking the head off the block. It could be warped, or it could be the gasket alone. You're looking at 500 for a salvaged cylinder head, 100 for the gasket set, and about 700 in labor and materials (i.e. anti-freeze).