The creation and manipulation of nanoparticles can result in unique optical properties often of no value in the fields where the particles are most commonly used. Sofie Boons, a London-based jewelry designer accustomed to working with gold, has applied these rare effects to beads used in jewelry.
“When I first heard about gold nanoparticles, I thought they would have a gold or a dark gold color,” said Ms. Boons, a recent postgraduate of London’s Royal College of Art. “Instead, they were purple, brown, blue or sometimes even edging on green. It doesn’t look like gold at all.”
The color of objects is usually determined by the absorption of light by the dye or pigment within the particular material. This color stays the same no matter which way the object is viewed or broken apart. Gold and silver nanoparticles create color differently. If a gold nanoparticle is broken apart, it turns into a new color. In collaboration with Jodie Melbourne, 26, a nanotechnology doctoral candidate at Imperial College London, Ms. Boons, 25, created a range of round beads to be incorporated in necklaces, earrings and rings. Using the color effect of gold and silver nanoparticles, the beads cast contrasting hues as the wearer adjusts their surroundings.
“If you have no light going through the bead, there will appear one color,” said Ms. Boons. “When you shine a light through the bead, its shadow will have another color. Then, when you hold the bead to the light, the light shining through will appear another color.”