The term oyster bar describes either an amenity

Amenity

In real property and lodging, amenities are any tangible or untangible benefits of a property, especially those that increase its attractiveness or value or that contribute to its comfort or convenience...

 within a restaurant

Restaurant

A restaurant is an establishment which prepares and serves food and drink to customers in return for money. Meals are generally served and eaten on premises, but many restaurants also offer take-out and food delivery services...

 or bar

Bar (establishment)

A bar is a business establishment that serves alcoholic drinks — beer, wine, liquor, and cocktails — for consumption on the premises.Bars provide stools or chairs that are placed at tables or counters for their patrons. Some bars have entertainment on a stage, such as a live band, comedians, go-go...

, or a category of restaurant that specializes in serving fresh oysters. The oysters are shucked on site and normally behind a counter, within sight of the customers.

The countertops are usually made of a non-porous easy-to-clean material, such as marble

Marble

Marble is a metamorphic rock composed of recrystallized carbonate minerals, most commonly calcite or dolomite.Geologists use the term "marble" to refer to metamorphosed limestone; however stonemasons use the term more broadly to encompass unmetamorphosed limestone.Marble is commonly used for...

 or granite

Granite

Granite is a common and widely occurring type of intrusive, felsic, igneous rock. Granite usually has a medium- to coarse-grained texture. Occasionally some individual crystals are larger than the groundmass, in which case the texture is known as porphyritic. A granitic rock with a porphyritic...

. Many oyster bars in America will have the ingredients needed for customers to make their own cocktail sauce

Cocktail sauce

Cocktail sauce is one of several types of cold or room temperature sauces often served as part of the dish referred to as seafood cocktail or as a condiment with other seafoods. In America it generally consists of ketchup mixed with prepared horseradish. Some restaurants use chili sauce, a spicier...

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