Arcane Experience is the Supernal equivalent to Experience
Five Arcane Beats become an Arcane Experience, in the same way five Beats become an Experience.
However, Arcane Experiences differ from normal Experiences in that they can only purchase magical traits.
In this context, this means Gnosis, Arcana, Praxes, and Legacy Attainments.
The costs are the same.
Also, note that Gnosis and Arcana can be purchased with mundane Experiences and any combination of mundane and Arcane Experiences.
Legacy Attainments have a prerequisite level of Gnosis.
A mage who invents her own Attainments rather than learning from a tutor may only spend Arcane Experiences to buy them.