Overview
Rune Prisms are gemstones modified to store and channel raw mana. They provide an important power source for Rune Gear Technology, supplying energy to machinery whose users do not need personal mana or knowledge of magic.
In Riseholm, Rune Prisms fuel airships and power the Clockwork Cathedral. Their wider uses include industrial machinery, automatons, communication equipment, tools, household devices, and equipment used in warfare.
Natural Gemstones and Preparation
Most Rune Prisms begin as natural gemstones modified by artisans and mages. The gemstones are normally cut down to a more solid form before their preparation as mana-storage components.
There is a theory for producing crystals artificially, but creating one requires immense pressure. The power required makes this an impractical production method. Natural gemstones remain the usual basis of Rune Prisms.
Preparing the gemstone brings material craft and magical knowledge together. The properties of the finished Prism determine the role it can serve in a Rune Gear device.
Size and Capacity
A Prism's size determines its mana storage capacity. Capacity concerns how much mana the component can hold for later use.
Some machines require a Prism of a particular size. The amount of stored mana is therefore one consideration alongside the machine's component requirements.
Purity and Usable Lifespan
Rune Prisms can be recharged and reused. Their purity determines how long they remain usable.
Refilling a Prism and replacing one are different tasks. Charging restores its mana supply, while its usable lifespan depends on the gemstone's purity.
Color and Mana Transfer
A Prism's color indicates its efficiency and mana transfer rate. These properties concern how it supplies mana to the device using it.
Color therefore has a practical role in selecting a power component. A machine may need a particular color because of its mana transfer requirements, even when another Prism meets its size requirement.
Charging Methods
Mages can charge Rune Prisms directly. In ordinary use, however, most charging is performed by machines that absorb mana from the environment.
The mana cost of charging is comparable to that of a lower-tier mage. Charging conditions depend on the mana available in the area: a mana-poor Node provides slow recharge or only small amounts of replenishment.
These charging machines connect Rune Gear's stored power supply to local environmental resources. Magic and Mana explains the wider rules governing those resources.
Machine Requirements
Prisms are selected according to the equipment they will power. Some machines require certain Prisms, particular sizes or colors, or a combination of those characteristics.
Size, purity, and color describe different aspects of performance. Storage capacity does not determine usable lifespan, and neither alone establishes the required mana transfer rate.
The user operates the finished device through its controls and functions. They do not need to supply personal mana or understand the magic within the Prism.
Failures and Node Conditions
Most failures produce sparks or smoke. Extreme failure can cause an explosion.
Nodes can also affect the technology that uses Rune Prisms. Environmental mana levels influence recharging, while other local rules can affect the operation of a device or its magical components.
Heavy environmental mana demand must account for local reserves. Depletion can recover naturally, while corruption requires intervention or a very long recovery period.
Rune Prisms and Relics
Rune Prisms are modified magical components. Storing mana does not automatically make an object a Relic.
Relics in Postremo Limine produce effects that ordinary magic, technology, or ritual craft cannot truly recreate. An ordinary Rune Prism supplies mana for a constructed system; its storage function is part of its magical craftsmanship.