The pastels are made in Northumberland and contain only pure pigments in a cycle of related hues, instead of adding white or black to the colours. The result is intense, vibrant colour not muddied by the blending of colours. Unison's pastels contain very little binder, making them truly soft and smooth. They are mixed to meticulous recipes and are based on traditional pigments such as cadmiums, cobalts and natural and synthetic earths. Pastels measure approximately 2-1/8in long × 5/8in diameter (54 mm × 16 mm). Sticks vary slightly due to the hand-making process.