Gothic tattoos can definitely identify a member of the Gothic subculture which is so popular nowadays. There are many stereotypes and associations (not always pleasant) connected to Gothic tattoos, but they are very beautiful, stylish (especially among the "carriers" of this subculture) and picturesque. Actually, the Gothic subculture has some prejudices associated with death, the special ideas about the definition of beauty. This prejudices are associated with the respect of the standards of this very "beautiful." The subculture carriers have an inclination to everything what is dark and dark aspects of the human mentality.
Ankhs and Gothic crosses are the popular Gothic tattoos in tattoo salon. Ankh is a Egyptian hieroglyph meaning "life", having a great contrast with the Gothic madness about death. In this regard, those who has serious superstition about death turn the ankh upside down to allude to the life's opposite. The Gothic crosses tattoos made in a tattoo salon are usually overly decorated, well thought out (and just beautiful). They exalt the beauty of death.
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Those who identify Gothic with something lofty, spiritual often put the pictures of bones, skeletons on their skin. The popularity of tattoos of this kind are the skull pictures which looks awesome, in case the tattoo is made by a real expert, and the bones pictures which can also look very cute.
Mythical creatures respected by the subculture are also a quite popular object of the Gothic tattoos. For example, different kinds of fairies, dragons, white rabbits are commonly accepted tattoos made in the tattoo salon among members of the Gothic subculture. Another popular choice is the wings of the fairies, dragons and angels on the back. It looks really cool. This is a tattoo salon portfolio.
Another Gothic attributes are roses (especially black), skulls and skeletons, spiders. Also Gothic vampire enthusiasm makes these creatures tattoos popular. These things are a generalization of what is popular among the Goths.
Obviously, the ultra-popular Gothic paintings are spread not only among the members of the subculture: the enthusiasts from all around the world use the Gothic motifs in their tattoos. Also the so-called "tribal" tattoos are popular, mainly because they are typically black and symbolic.
Gothic tattoos are endless. If you are a member of the subculture, then the only limits are set by the flight of your imagination. If you just want to accentuate your personal style - I advise you to read up on its symbolism.