A continuous belt casting apparatus is provided with a casting cavity, and at least one flexible metal belt having an elongated casting surface passing through and at least partially defining the casting cavity. A motor is provided for rotating the metal belt in the longitudinal direction of the casting surface whereby the casting surface passes through the casting cavity in the longitudinal direction. A molten metal supply device delivers molten metal continuously to the casting cavity, so that molten metal supplied to the casting cavity is solidified and removed as a continuous strip ingot from the casting cavity by rotation of the belt. The casting surface is provided with a plurality of grooves oriented in substantially the same direction. The invention also relates to a casting belt for such an apparatus and a method of casting using the apparatus.