Although very similar, buckles are characterized by a cake with any fruit. Whereas coffee cakes are any cakes that are intended to be served with coffee. Blueberry Buckle has a denser texture compared to coffee cake. It is often made with thicker batter that incorporates blueberries throughout, but tend to sink to the bottom during baking, creating a jammy layer at the base of the cake. The fruit in a coffee cake is suspended throughout when the cake is baked. The other major difference is that coffee cake is usually topped with a streusel mixture. Buckle recipes sometimes have a topping, but it isn't a component of the traditional recipe.