Pieridae Geometric Yellow Blue Core Patchwork Effect Duvet Quilt Bedding Cover and Pillowcase Bedding Set. Sleep tight with our Geometric Core Duvet set that will transform your bedroom into a stylish sanctuary. The Geo Core features a patchwork effect triangular pattern in striking blues, greens and yellow against a white background. Fully reversible with a triangular background, this cool set would make a great gift for a loved one! This is one bedding set you will not want to remove. Made from cotton and polycotton and the bedding set is machine washable at 40 degrees and suitable for tumble dryers.