Memory Stones are resource-type items that can hold spells or heat.
Empty Stone[]
Memory Stones can be harvested by a Memory Stone Collector and will behave as regular resource, meaning they stack up and can only be traded as batches. When a magician gets a hold of them, they can be separated again and charged with a spell. This only works when the magician has at least 5 casts as the spell's maximum and more than 80% of the total casts left. This process depletes the casts of the magician completely.
Enchanted Stone[]
Once this is done, the stone turns into an 'Enchanted Stone', which can be traded separately and is a consumable item with 1 use. The player using it learns the memory that was imprinted in the stone with 2 or 3 non-regenerating casts. These casts stay with the player until they are used up, or until 6 months passed by.
Upon use, the stone shatters into timeless dust, a resource-type item.
Heat Stone[]
If a Fusioneer gets a memory stone, they can charge them with heat from heat jars, using a special tool. This turns them into a Heat Stone.
They can either be used to learn the spell Heat or to store heat to later heat devices such as tools, or cauldrons. Just like an enchanted stone, the heat stone shatters after use.