The Gerona classic storm lantern is handcrafted to utmost perfection. They are made of free-blown clear-glass. These storm lanterns can be used with various pillar candles. To avoid having to keep an eye on the burning candle, put some fine sand or water in the bottom of the glass. This will reduce the danger of the glass cracking when the candle burns down. Clean your storm lantern by hand with warm water and dishwashing liquid.