Abstract: A device able to generate electrical power through relative rotational motion of first (370, 380) and second (200, 230) principal components around an axis of rotation (220); wherein: the first and second principal components comprise an arrangement of piezoelectric elements (380) and permanent magnets (230, 370) such that the interaction between these magnets and piezoelectric elements, in use, makes it possible to generate electricity; and wherein: the second principal component (200, 230) comprises a center of mass offset from the axis of relative rotation (220) such that the response of the second principal component (200, 230) to either gravitational or inertial forces is a relative rotation of the second principal component (200, 230) in relation to the first principal component (370, 380); the first principal component (370, 380) being fixedly attached to the moving host structure (100).

Abstract: A device able to generate electrical power through relative rotational motion of first (370, 380) and second (200, 230) principal components around an axis of rotation (220); wherein: the first and second principal components comprise an arrangement of piezoelectric elements (380) and permanent magnets (230, 370) such that the interaction between these magnets and piezoelectric elements, in use, makes it possible to generate electricity; and wherein: the second principal component (200, 230) comprises a centre of mass offset from the axis of relative rotation (220) such that the response of the second principal component (200, 230) to either gravitational or inertial forces is a relative rotation of the second principal component (200, 230) in relation to the first principal component (370, 380); the first principal component (370, 380) being fixedly attached to the moving host structure (100).

Abstract: An article of jewelry arranged to simulate natural optical effects, such as sparkle and scintillation, is described. The article comprises a jewel, such as a brilliant cut diamond and one or more light sources, such as colored LEDs, incorporated in the article of jewelry for emitting light so as to illuminate the jewel. The article also comprises a microcontroller for driving the one or more LEDs to cause them to emit light pulses of varying intensity thereby simulating said natural optical effects of the jewel. The duration of the light pulses and the location of each light pulse can be varied to enhance the artificial illumination. The article preferably has a cordless rechargeable power supply which avoids the need for unsightly electrical contacts by using an inductive loop charging circuit.