Resin is the oldest form of incense there is: hardened tree sap, burned on heat rather than lit directly. It produces the heaviest, most enveloping smoke of anything in this category, and it needs more setting up than a stick.
How to burn it without scorching your table
Resin does not light. It melts and smokes when heated, so it needs a charcoal disc in a heatproof burner.
- Fill the burner with sand or ash to at least a centimetre. This insulates the base — a charcoal disc runs far hotter than most people expect and will crack a bowl set directly on a surface.
- Hold the disc with tongs, not fingers. Light the edge; it will spark and travel across. Self-igniting discs contain saltpetre, which is what makes them catch so readily.
- Wait until it is ashed over grey. A disc that is still black is too hot and will burn the resin rather than melt it, which smells acrid.
- Then a few grains of resin on top. A few. Resin goes much further than people think.
The common resins, briefly
Frankincense — from Boswellia. Bright, citrusy, slightly peppery. The one most people mean when they say church incense.
Myrrh — from Commiphora. Darker, bitter, medicinal. Traditionally burned with frankincense rather than alone, because alone it is quite austere.
Benzoin — sweet, vanilla-ish, and the gentlest of the three. A good first resin if the others feel too heavy.
"Amber resin" is a blend
Worth saying plainly: the amber resin sold for burning is not fossilised amber. Fossil amber is a gemstone, it is expensive, and burning it would be an odd thing to do. What is sold as amber resin is a compounded blend — usually benzoin and labdanum with fragrance — made to smell like the accord perfumers call amber. It is a perfectly good product under a slightly misleading name.
Ventilation
Resin smoke is dense. Considerably denser than a stick. A window open is not optional in a small room, and a smoke alarm in a hallway will find it.