Is onyx the same as jet?

No. Jet is fossilised wood (organic), onyx is a mineral quartz variety. Visually, however, the two are easily confused. Onyx is distinctly colder in the hand, harder (Mohs 7 against 2.5–4 for jet) and takes a higher lustre after polishing.

Why did onyx come into use only in the second stage of mourning?

The Victorian court mourning code forbade any lustre in the first stage of mourning - onyx, with its strong polish lustre, was therefore too "lively". Only in second mourning were lustrous black materials permitted; there onyx became the principal stone.

Is onyx widely traded today?

Yes, above all in the mid-price segment. Onyx is robust, skin-friendly and retains its polish. In modern memorial jewellery it appears as a cabochon in rings and pendants, increasingly also in combination with laser engraving or as a ground for fingerprint inlays.

Onyx

Onyx is a black variety of chalcedony which, in Victorian mourning jewellery of the second stage of mourning, formed the lustrous, polished counterpart to matt jet.

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