Counterfeit banknotes

Have you ever seen banknotes being checked in a shop? They are put into a box with a violet lamp. If they are real they glow with little ribbons and straps.

All these phenomena make use of ultraviolet light. The light of quartz lamps may burn your skin. 10% of the Sun light is ultraviolet. It's not much but still it is dangerous.

In Poland, 80% percent of holiday-makers are said to sunbathe so much that they risk developing skin cancer.