Buying Whitby Jet Without Getting Caught

Walk the length of Church Street and roughly every second window has black jewellery in it. Some of that is Whitby jet. A good deal of it is not, and the difference is worth several hundred pounds.

What jet is

Whitby jet is fossilised wood. Specifically it comes from the Jet Rock unit of the Mulgrave Shale, part of the Whitby Mudstone Formation, laid down roughly 181 million years ago in the Toarcian age of the Early Jurassic, from trees related to the monkey puzzle that still grows in Chile. The deposit runs through the cliffs and moors of this coast and nowhere else in Britain produces it in this quality.

Technically it is a lignite, the lowest rank of coal, and a mineraloid rather than a mineral. Practically, what matters is that it is very light, warm to the touch, and takes a deeper black polish than almost anything else that can be carved. It is also soft, roughly 2.5 to 4 on the Mohs scale, which is why jet jewellery scratches and why an old piece with a perfect surface should make you look twice.

Why the Victorians bought so much of it

Jet had been worked here since Roman times, and in the Viking and medieval periods after that, but the Victorian mourning trade turned it into an industry. Queen Victoria wore a jet necklace as part of mourning dress in the 1850s, and wore Whitby jet again in the long mourning that followed Prince Albert's death. Court mourning had rules, and jet satisfied them: black, sombre, and, being light, wearable in quantity.

The trade peaked in the early 1870s. Whitby had over a thousand people working in jet at its height. Then fashion moved, Art Nouveau had little use for black jewellery, and the numbers collapsed: down to about three hundred workers by 1884, with the remaining makers largely sticking to old designs rather than adapting, which accelerated the fall. Tourist trinkets kept a handful of jewellers going, but by the end of the Second World War only three were left, and the industry died out completely with them.

What exists on Church Street today is therefore a revival rather than an unbroken line. That is not a criticism. It does mean that a shop's claim to be continuing a family tradition deserves the same scrutiny as any other claim.

See it worked before you buy it

The most useful thing you can do before spending money is watch the stone being cut. The Ebor Jetworks, at 138 Church Street, is a family workshop that makes its jewellery on the premises and offers a free Whitby jet working demonstration through the day, which is the closest you will get to seeing the Victorian trade's actual craft rather than its output. Two other places fill in the context. W Hamond's Museum of Whitby Jet occupies the restored Wesley Hall on the same street, which the firm took over in 2015 and which now holds its jet collection and archive. Whitby Museum, up in Pannett Park on the West Side, has jet and the tools of the Victorian trade in its cases alongside the local fossils.

Twenty minutes in any of them will teach you more about what you are looking at than an hour of window shopping.

Telling the real thing from the rest

The substitutes are old and numerous: black glass, often called French jet, which is not jet at all; onyx; vulcanite; bog oak; and, in the modern era, moulded resin. A few practical checks that experienced buyers use, none of them individually conclusive:

• Weight. Real jet is startlingly light for its size. Glass and onyx are noticeably heavy.
• Temperature. Jet is warm to the touch almost immediately. Glass and stone stay cold.
• Surface. Jet is a fossil, so under a loupe you can often see grain and small irregularities. A perfectly uniform surface with a mould seam is resin.
• Sound and feel. Jet has a soft, slightly plastic feel rather than a hard glassy one.

Do not scratch or streak-test anything in a shop, which is both rude and destructive. Instead, ask. On Church Street, asking to see a piece under a loupe and asking directly whether it is Whitby jet, as opposed to jet from elsewhere or a substitute, is completely normal and will be answered straight by anybody worth buying from. A dealer who is evasive about provenance is telling you what you need to know.

Where to buy

The established Church Street jewellers are the safe route. W Hamond, at 112 Church Street, trades as the original Whitby jet store and dates itself to 1860, which places it in the middle of the boom. There are several other long-standing workshops and jewellers along the same street, and the workshops in particular will usually tell you exactly which piece of coast a stone came off.

Antique jet is a separate market with separate risks. Victorian pieces are widely available and widely faked, and condition matters a great deal on a stone this soft. If you are spending seriously, buy from a specialist and get it in writing.

And if you just want the thing itself rather than the jewellery: the fossil-rich shale on this coast gives up small pieces of jet, ammonites and belemnites to patient beachcombers, particularly after a winter storm. Check current rules and safety guidance before collecting, keep well away from the cliff faces, which are actively eroding, and be honest with yourself about how much of what you find is jet and how much is ordinary coal.