Granite is a popular material for the countertop. Granite has the advantage that is unique, hard, durable, scratch resistant and easy to clean. However, with these advantages, the granite is expensive. Because the price is quite expensive, then it needs to be careful when deciding to use the sink which is what it looks like.
Combining granite with sink to match the granite top is not too difficult. Play with the color theme, the contras or similar. The sink can be used as an accents to the theme of your kitchen cabinet. If you want to be safe, use a similar color.
Material for the kitchen sink are ceramic, stainless steel, composite, plastic, concrete, copper. As for the bathroom is a lot more of that stuff, because it takes decorative form. To get more than just the function, to consider the combination of the shape, materials and additional feature, but you will be reaching into the pocket deep more.