Effects

Effects are part of the item and spell system. Essentially they are enchantments that are powered by properties. Each enchantment takes one or more properties to power it. Properties can come from items, buildings, creatures, or spells. You may require a long chain of effects that produce different properties to reach a final result. For obvious reasons mana generation is the most powerful property. If you need heat for something you can own a material or creature that innately generates heat or you can create heat through magic.

Suppose you wanted to alter the climate of a province to be more comfortable for your species or for other reasons. Like terraforming icy tundra or something. You could create a great artifact that has a massive and powerful heat aura. You would need a magical item/building that could project an attribute, in this case heat. How you supply the heat is irrelevant to the item/building. So if you had a way to create heat that didn't involve a magical effect drawing mana you could use that. Perhaps you could awaken a slumbering volcano and drain its heat to your device rendering it harmless while providing what you needed. In most cases you would probably use raw mana, though, as its very flexible.

Other effects might involve some sort of plant growth boosting aura, a darkness or light generator, a cold generator, maybe you use it to preserve food rather than chill a whole region. The majority of these effects would involve a magical spell somewhere in the chain. A material that naturally generates heat or cold would be useful for cooking or storing food and not require a mana conversion, though.