Stick incense is bamboo rolled in a paste of resin, wood powder and fragrance oil, which is why it burns evenly and for a set time. Resins such as frankincense and copal are the older form and need a charcoal disc in a heatproof burner rather than a stick holder. Whatever you burn, do it in a ventilated room, keep it well away from anything that can catch, and never leave it unattended. A heatproof surface under the holder saves a lot of bother. Hand-picked in St Andrews and posted UK-wide.