The most striking feature of the Blue Oil Fern is the iridescent blue colour to some of the leaves. It is believed that this colouration helps the plant obtain more light in the jungle canopy.
This plant is fine in low light however does prefer higher humidity. It needs to be kept dry, if it is overwatered it will lose its frond.
These plants are epiphyte (grow on other plants) so are great for mounting onto moss boards in a humid cabinet.
Some marking to largest frond hence the lower price.