Caffeine is a natural stimulant found in coffee, tea, and other foods. It blocks adenosine receptors in the brain, reducing fatigue and increasing alertness and concentration. Necklaces and earrings that are really taste-ful. Available as necklace (see separate listing) or pair of earrings, in a bag or presentation box. Earrings have a drop of 2"/6cm with hyper-allergenic silver findings The Earrings are available in a choice of 7 colours - hand-dyed for uniqueness using Carbon-neutral 3D printed nylon.