In its late nineteenth century synthesis the Hermetic Order of the Golden Dawn adapted Akasha into a black or deep indigo egg shape, the last and subtlest of five coloured meditation cards that make up a Western practice separate from the tattva's role in Indian philosophy. The egg or oval form, unlike the four geometric shapes assigned to the other tattvas, was chosen to suggest a boundary containing all possible form without itself being one fixed shape, consistent with Akasha's place as the field the other four elements arise within.
Golden Dawn method has the practitioner gaze at the painted shape until an afterimage forms, then hold it with closed eyes as an entry point into meditative states, typically treated as the deepest or most difficult of the five cards to work with; the practice passed into later currents drawing on Golden Dawn material largely unchanged.
This gazing technique is a distinct later invention and should not be mistaken for Akasha's role in its own tradition, where the tattva names the subtlest of the five gross elements, tied to sound and to the space within the body, the ground from which the other four are said to unfold, a metaphysical claim with no original tie to a painted egg used for scrying.