Granite
Formed by volcanic activity, granite is one of the hardest and least porous rocks you can use for a countertop, which is why it is the most popular stone surface for both interior and patio kitchens. It is fairly resistant to acidic products and requires only an annual resealing.

It has two kinds of color patterns: One is consistent, meaning it has the same speckled pattern throughout; the other is variegated, with veins that swirl and vary from slab to slab.

All granite consists of a percentage of crystals, which shimmer when hit by light. It is generally polished but can be honed for a softer finish or sandblasted for a rougher one.

Marble
Characterized by deep or light veins that can vary dramatically from one slab to the next, marble is softer and less dense than granite. Its color range is dramatic, from soft beiges to pinks, dark reds, oranges, and greens. Because of its color, even a small area of marble can make a large design statement.

Consider marble if you don't mind a high-maintenance material. Food acids such as lime and vinegar will stain and etch it quite easily, so the surface must be resealed frequently. However, you might like the aged quality that staining creates and want the look for your kitchen. Serious bakers often insert a section of marble in their countertop because they consider it the ideal surface for rolling out pastry.

Marbles vary in softness, so check with the supplier to make sure the one you like is suitable for your situation. Marble is available polished, honed, and tumbled.

Travertine
Less formal than marble, travertine is characterized by small pits scattered across its surface.
The stone tends to be fairly soft, and the pits can soak up moisture and stains. The slab can be honed, however, filled with grout, and then sealed to preserve the surface. The warm tan hues and soft feel may make it worth the extra maintenance.

See More about Other Countertop Materials