Cognizant

The viking compass stone — it tells you where the light is coming from.

Iolite · The Law of Purview

Family: Cordierite — Mg₂Al₄Si₅O₁₈
Hardness: 7–7.5 on the Mohs scale
Colour: Violet-blue one way, pale honey-grey the other
Signature: Strong pleochroism — three different colours from three directions

The stone read as the word

Iolite shows a different colour from every axis, and Norse navigators are said to have used thin slices of it to find the sun through cloud. Being cognizant is exactly this instrument: knowing your position because you can read the light you cannot see directly.

Cut wrong, iolite goes grey and dull. The gem depends entirely on the cutter having oriented it correctly. Awareness has an orientation too.

What it is carried for

Carried by the one who is responsible and knows it.
Held for taking a bearing before moving.