Whitby Jet is an amazing substance which has its imitators. As a lot of Whitby Jet jewellery has become very valuable in recent times I have produced this web page to try and help you to recognise genuine Whitby Jet from fake.
I cannot guarantee to give you 100% proof that an item is genuine, there are a lot of variables involved. Hopefully, with a few pointers, I can guide the uninitiated to recognise the obvious fakes.
Whitby Jet is BLACK - there is no getting away from it "JET BLACK" so if what you are looking at isn't black then it is not Jet.
Whitby Jet, when polished has a beautiful sheen, not as harsh as a reflection from glass, more of a glow.
Handle it. Jet is surprisingly light in weight and feels warm to the touch.
Glass (sometimes called "French Jet") Is heavy and cold to the touch and has a 'glaring' reflection.
Vulcanite/Ebonite is a deceptive early plastic, it is lightweight and warm to the touch. It doesn't have the sheen of real jet and in time turns from black to brown/khaki in colour.
Coal is cold to the touch and very brittle.
Bog Oak ancient black wood, unfortunately has all the characteristics of jet, you will have to wait for the 'Red Hot Needle Test' for this one.
Modern Plastic is too shiny and usually has 'moulding' marks which give it away.
The Red Hot Needle Test
The definitive way to test for genuine jet.
The only problem with this is you must know what burning coal smells like. No problem for oldies like me but how many of todays kids have smelled burning coal?
OK - this is what you do.
First get a large darning needle, bodkin or piece of thin metal rod, heat the tip until it is red hot and then touch it onto the piece you want to test. You should get a small puff of smoke which smells very similar to burning coal but more 'tarry'. Of course it may be coal - go on to the 'Streak Test'.
Vulcanite/Ebonite will give a smell similar to burning rubber, glass will not melt or burn, bog oak will smell of burning wood and plastic will melt and smell of burning plastic.
Note. The item you are testing may well be a valuable antique so be careful where you apply the needle. The back or side of the item is best or if you are testing parts of a necklace or bracelet you could use the holes (be careful not to damage the elastic or string).
The Streak Test
Don't panic - you keep your clothes on for this.
When most substances are scraped across a piece of unglazed porcelain they will leave a 'streak', this streak may be a different colour from the original substance. In the case of Jet the streak will be dark brown, coal and plastic leave a black mark, glass will not leave a streak but unfortunately Vulcanite/Ebonite also leaves a brown mark.
So, obtain a piece of unglazed porcelain (the back of a ceramic tile is ideal) and scratch a small part of your suspect item on it (preferably part that will not show). Examine the colour of the mark which has been left. As Jet leaves a dark brown mark it may be an idea to put a line from a black marker pen on the tile to compare the colours.
Here is an example of the different streaks obtained
3 Black Plastic
5 Black Marker Pen