Is your £50 note a fake? The test
The good news is that the new notes have been fitted with some very cunning technology to protect you.
Security featuresAmong the coolest is something known as a 'motion thread'. This is woven vertically into the the paper. You can see the thread at five points along the note, and at each one you should be able to see a £ image.
If you tilt the note, it will change to a 50 image. However, the way the image changes will depend on the way you tilt the note. If you tilt it from side to side the images change up and down. If you tilt it up and down, the images move from side to side.
This is in addition to a portrait of the queen, which appears when you hold the note up to the light, and the number 50 which appears when you hold it under ultra-violet light (if you happen to have one handy). Under this light you will also see green and red flecks scattered across the note. The security features can be seen in this report from the Daily Mail.
Changing notesThe notes, which also feature portraits of Matthew Boulton and James Watt, responsible for the development of the steam engine, have already started hitting the streets, and will be distributed for the next couple of years. At that stage you won't be able to use the notes in shops and banks - you'll have to send them to the Bank of England.
The risksIt's worth bearing in mind the new security devices if you are ever faced with one of these notes, as if you accept one and then discover it is a fake, you will not be compensated by anyone. Anyone who receives a fake note and then attempts to spend it is actually breaking the law, so the risks are very serious indeed
Counterfeiting may be decreasing as notes get more sophisticated, but still in 2010, there were 300,000 discovered by banks - with a value of £5.9 million. It therefore remains a risk that we must all be alive to.
So even if you imagine your chances of receiving a £50 are about as high as you receiving an OBE, it's worth remembering the tests and what to watch for, just in case.