18kt recycled yellow gold 18kt recycled yellow gold CELESTE laboratory-grown diamond clasp chain necklace from Courbet featuring signature CO motif chain, laboratory-grown diamonds, rear toggle fastening and gold weight 24,1g. POSITIVELY CONSCIOUS: This Planet Conscious product is crafted from certified recycled or upcycled materials, which helps you make a better choice for the environment as they generate less energy, save water and reduce the need for new raw materials. For recycled synthetic clothing products we highly recommend using a microfibre-catching washing bag to ensure that no microplastics that can pollute water are released in the process..