Geodes are items that raise the enhancement level of a weapon or an armor piece. There are two types of geodes, spiral geodes and vortex geodes. Spiral geodes increase the level by +1 up to their listed enhancement level with no materials and zero failure chance (for example, a +6 item would be raised to +7 by a +7 Geode). Vortex geodes increase the level to match their own level (i.e. a +7 Geode will raise any +6 or lower item to +7, whether it's +6, +0, or anything in between), again with no materials and zero failure chance. They are used in the same manner as Sparks.
These items are obtained by dismantling an enhanced piece of equipment using an Extractor. The equipment's enhancement level determines the enhancement limit of the Geode while its rarity determines the rarity of the Geode. Unenhanced items do not yield Geodes when dismantled. In addition, Blacksmiths can exchange a large quantity of Comet Dust for a bag containing a random Spiral Geode, or a large quantity of Sun Powder for a bag containing a random Vortex Geode.
Geodes are slot-specific (e.g. a Glove Geode can only be used on gloves) and are limited to their corresponding rarity: rare geodes are only for Rare equipment, while epic geodes are only for Epic equipment; there are both spiral and vortex geodes for both rarities.
In cDN, Spiral Geodes are only for Rare equipment while Vortex Geodes are only for Epic equipment; they both function like spiral geodes, despite the name. They also have a maximum level limit for the equipment they can improve.