Pearlwort

The Pearlwort, or the "Colobanthus quitensis", is one of the native flowering plants found in the Isbreen region. It has white flowers and grows about 5cm (two inches) tall, with a cushion-like growth habit that gives it a moss0like appearance. This plant also has a parasitic counterpart that is very rare in the harshest areas of Isbreen. these plants are scientifically known as hemiparasites and can photosynthesise but also drain water and nutrition from its hosts. Fun fact, other parasitic plants, known as holoparasites, cannot photosynthesise and depend on their hosts for food.
Speaking of hosts there seems to be only one other plant that the Pearlwort seems to favor as its host. Introducing another native flowering plant the Hair Grass, or the "Deschapsia antarctica", this clump of grass is famous for growing on top of boulders infused with ice. Not onl do these boudlers contain water but the natural minerals within the rock is able to sustain this plant's life.
With an abundance of nutrients the parasitic Pearlwort, or in other words, the Pearlcrown,rests on top of the hair grass and begins to drain its hosts till there is nothing left. The result of all the minerals in the boulder also tend to change the Pearlwort's beatuiful white color into a deep dark black that makes it into the Pearlcrown we know. Note that Pearlcrowns are also used in alchemy to create Cold Resistance potions these potions allow any creature that drinks it a prolonged immunity to servere freezing temperatures. The effect on the potion depends on the number of Pearlcrowns used in the batch and the potency of how healthy the plant was on harvest. However, these potions also come with a huge drawback for having such a useful buff. When consumed these potions tend to resemble its previous parasitic nature and proceeds to cause the consumer extreme dehydration and hunger.