What does a skull and cross bones on a headstone mean?

Hi there. In my line of business people often ask about symbolism and what it means when certain things are inscribed on a gravestone. Generally, the skull and crossbones just stands for mortality or death while a skull with wings refers to ascension to heaven. There are many gravestone symbols that through symbolism make a statement about the person buried there. For instance, a engraved Easter lily symbolizes purity.