Why the glass is amber

Dark amber glass reads as a design decision. It began as a functional one.

Botanical oils are photosensitive. Ultraviolet and short-wavelength visible light drive oxidation, which changes scent first and performance second. A rosemary or geranium oil that has stood in clear glass on a bright shelf is no longer the oil that was filled.

What the glass does

Amber filters most of the ultraviolet and blue end of the spectrum before it reaches the formula. It is not a perfect barrier — nothing transparent is — but it buys the product the months between filling and the last application.

Why not opaque

Because you should be able to see how much is left, and because the material is worth seeing. Thick amber glass has weight and depth; it holds light rather than blocking it. Set against a matte black closure and an uncoated ivory label, it does the work of the identity without the identity having to say anything.

Store it out of direct sun regardless. The glass slows the process. It does not stop it.