You are at a car boot sale, you pick up a piece of black jewellery, but you don't have a red hot needle or a piece of unglazed porcelain with you. So - what do you look for?
The item is black, light weight and warm to the touch. There
is a good chance it is jet.
Fortunately jet jewellery has its own peculiar characteristics
which we now have to examine. You may need a magnifying glass
handy.
Wood Grain
As jet was originally wood it may just be possible, on close
examination, to spot the wood grain on a polished piece of jet.
The rear of flat items such as bracelet sections, pendants and
flat sections of necklaces are the best places to look, you are
unlikely to see the grain in beads
.The photograph is greatly enlarged and the contrast has been
increased to show the grain which runs from left to right in this
piece.
Plastic, vulcanite and glass do not have a grain, coal and bog oak do.
Damage
Although we don't want damaged items, one aid to identifying jet is the way the it becomes damaged. Old jet in particular may have cracks and chips which can be a clue to its identity.
Conchoidal Fractures
The word conchoidal means 'shell shaped' and on older jet jewellery you will often find these fractures. Commonly referred to as "nibbles", "nips", "chips" or "flea bites", they can usually be found near holes or on the edges of items.
Sometimes the fractures may have formed whilst the item was being made in which case they may have been polished and have a smooth appearance.
Cracks
Due to its origin as wood, jet can form cracks along the wood grain. Beads and thin pieces of jet are more at risk of cracking than the thicker pieces.
Carving and patterns
Jet is a solid and therefore cannot be put into a mould and shaped. All the shaping, carving and engraving had to be done by hand and is therefore very 'sharp' with flat facets and very fine detail. Jet can also be 'undercut' giving better 3 dimensional carvings whereas moulded items cannot be undercut.. Glass, vulcanite and plastic can all be moulded and retain give away signs of the moulding such as rounded edges, poor quality patterns and moulding marks.
Jet
The carving on jet is usually very deep and patterns sometimes have slight errors as they are hand cut.
Beads
These are amongst the most common designs for necklace beads. The jet beads usually have very deep carving or large facets.
Fasteners
Due to the somewhat brittle nature of jet, the fasteners on brooches and pins tend to be very large and glued on with black glue.
Necklaces had a variety of fasteners, mainly 'hook and eye' or 'barrel' style.
Some of the heavier necklaces and chokers used ribbon as a fastener.
Unfortunately the fasteners on necklaces quite often break or the necklace is restrung and the fastener replaced, the 'hook and eye' type are usually original but even that can not be a guarantee of authenticity. The 'barrel' fastener picture above is a modern one.
Chains
Because jet is solid and cannot be bent or moulded all jet chains are made in a particular way. The shapes are cut and drilled then alternate ones are cut in half, have metal pins inserted, and then reassembled through the next piece (which hasn't been cut).
If a chain has links which are only cut in one place then they have to be made of vulcanite or plastic, they cannot be jet.
Enough!
If you cannot identify genuine jet by now then
I give up!
On page 3 are some examples of 'Not Jet', I will give you
clues about what they are,
then go to the bottom of the page to find the answers.
