These black and gold candle vessels are made from Jesmonite which is a eco-friendly material, similar to concrete but much smoother. Please note that these are not reusable as the wax might stain the vessels while burning. We recommend you to do a burning test before selling so you can adjust your wick accordingly to the vessel dimensions. The vessels are sealed with a wax sealer on the outside and a heatproof sealer on the inside. Please note that they're not waterproof, but watersplash proof. If it gets in contact with water wipe it with a dry soft cloth and let if fully air dry. The products are made on order and because of the nature of the material some air bubbles might occur. These doesn't take away the beauty or the functionality of the product. Comes with rubber feet to protect the surfaces. If you'd like any other colours please let us know ☺️