Countertop material for the island doesn't have to match the rest of your kitchen countertops as long as it is harmonious with the room's overall design. You may want to splurge on solid surfacing here, for example, and use laminate on the other countertops. A butcher-block countertop is ideal for chopping, while granite or marble works well for baking purposes and for rolling pastry dough.
We are often asked if the countertop of the island needs to match the existing kitchen countertop in style, or what will be installed as the main kitchen countertop. In most homes I would say it does match, but it really does not have to at all, nor does the material need to be the same. In fact, if you are not going to match them up exactly it's better if it looks like you are not even trying to match them, so using a completely different color and surface is perfectly acceptable.
A kitchen island is one of the best investments you can make in your kitchen. Not only does it serve decorative purposes, but it also offers numerous functions for home owners. First and foremost, it can enhance the interaction between the cook and the guests.
Maximize natural light by having windows and skylights, and keep kitchen wall surfaces light in color to reflect daylight. Custom kitchen islands work great by using pendant or recessed fixtures to direct light onto the kitchen island and other work areas. Electrical codes will likely require that electrical outlets be located on the sides of fixed kitchen islands, not on the top, to prevent electrical shock.