The element we commonly associate with salt - and keeping an eye on our diet so as to not get too much to save us from high blood pressure - is to most just a chemical with a name with relatively few being aware that it is a shiny metal that looks just like silver. Except it's so soft that it can be parted with a fork. And on exposure to air that silver sheen turns to muck in a matter of seconds. In water, as you can see thanks to a million YouTube videos, it quickly goes from hissing to a fiery *KABOOM*. In fact, it is so reactive that even in mineral oil, the chemical industry standard for inert storage, still has enough stray atoms of something-other-than-oil that they're enough to spoil that beautiful finish. Our high-grade mineral oil coats this small sample to stop the corrosion to the thinnest possible depth preserving the bulk of the specimen. The whole floats in a stiff gel within the labeled cube meant for our medium display case but which also makes for a handsome display on its own.
This sliver of sodium metal is kept permanently free of oxides thanks to the little ampule that holds it. The natural color of sodium is white but the heat of sealing has given the glass a coppery tone.