|Data Value||dec. 2415|
|Mod Included||ThaumCraft 2|
Vis Crystals are magical energy in a condensed and pure form.
Occasionally one can find natural crystals of pure Vis deep underground. These slowly grow over time into larger crystals, but only in areas where the aura has a positive charge.
The crystals themselves have no effect on the local aura, unless the aura in the area becomes extremely low. In that case trace amounts of Vis are released from the crystals which may cause the aura to replenish at a slow rate. However, Aura growth from crystals only occurs when the Aura or Taint dips very low (below 10% of max, which equals about 1500 Units of Vis or Taint). However, harvesting crystals actively damages the aura. Harvesting Tainted crystals however, will boost the aura.
Vis crystals have a myriad of uses which makes them a highly sought after resource. Care must be taken not to over-harvest them however, since doing so causes instability in the local aura which might lead to an increase in Taint level. Without the crystals the aura also cannot replenish should it drop to low levels.
There are six types of crystals:
|Vis Crystals||Vaporous Crystal||Aqueous Crystal|
|Earthen Crystal||Fiery Crystal||Tainted Crystal|
It is also possible to craft a place-able version of the Vis crystals called "Vis Ore" if you have harvested enough of the individual crystals:
This recipe works for all types of crystal. As long as it is placed on a solid surface and the Aura level is high enough, it will grow and behave as a normal crystal. You can use this in order to cultivate the crystals. Once a seeded crystal sprouts two or more crystals, you can use a Crystalline Bell in order to remove single crystals without damaging the seed.
Also, if you encounter crystals while mining and are not in immediate need of them as crafting or alchemy supplies, you should consider marking the location and picking them with the Crystal Bell instead of harvesting them with pickaxe. This way you can come back later to harvest the regrown crystals again.