We use French jet, which is black glass that can be faceted or plain. French jet was used in the Victorian era as a less expensive alternative to Whitby jet and is very popular today. The jet found at Whitby in England is of early Jurassic age, approximately 182 million years old. ]Whitby jet is fossilized wood and was popularised by Queen Victoria, who wore Whitby jet jewellery while mourning the death of her husband, Albert.