Onyx

From the Greek "onyx," meaning "nail." In myth, Cupid trimmed Aphrodite's nails, and the clippings turned to stone.

A variety of chalcedony. Most commonly seen as solid black, though true onyx carries black and white banding. Since Roman times, that banding has been carved in relief to produce cameos—the natural contrast between layers used directly as light and shadow. The structure of the stone became the medium of expression.

Found in Brazil, India, and Uruguay. One of very few stones used without interruption from antiquity to the present.

In a season where the centre keeps drifting, the fix has to come from inside — not external bracing. This stone is for that internal reset. The density of the black becomes the density of resolve. That sounds like a line from somewhere it shouldn't, but pick it up and see if the sensation disagrees.