We found these excellent jewellery items being made by the lovely people at Yellow Owl Workshop, and we've picked out our favourite mathematical jewellery for you.

All items come packaged in a funky glass jar, and this You ∩ Me Venn Diagram pendant necklace would make an ideal gift for someone you'd like to intersect with. It's made using cloisonné enamel on gilded luminous 22-karat gold, with a soldered 18-karat gold dipped chain. Each pendant is about 1" (2.5 cm). Chain is 18" (76 cm) long with clasp.

Price = p₂₇₈ pence = £17.89