tattoo over birth mark or beauty marks an such

just wondering can you tattoo over a beauty mark/mole/birthmark at all? i see in some pictures that they arnt touched, and others are.

I have tattoos over a birthmark, but, tattoos AROUND moles. Esp, if the mole is "raised", I can't imagine tattooing OVER it. I don't know what a professional would say though:) (I also have tattoos over scars) However, You can't notice my mole in the middle of the rest of the tattoo, as it was easily hidden...I guess it depends on what your mole LOOKS like, eh? It might be finve inches wide, and tall, and growing hair like a witches face:)

im just curious, im doing an apprenticeship. i havnt asked the person teaching me yet just cause my girlfriends brother asked if he could get one over his birthmark. its pretty dark and if so, would haver to be black, but just asking differant opinions and everything or if people have gotten any.