The magnets are quite brittle. Don't let them fall on to hard surfaces (like concrete) from a height – they may shatter into sharp pieces. Straight copper pipe, at least 30cm long. 15 or 22mm ...

If the material is the color of a penny (dull brown or greenish) and a magnet does not stick, the pipe is copper. If the material is dark yellow or golden, the pipe is brass. If the material is ...

If the magnet does not stick to the pipe, residents are asked to scratch the pipe with a penny or other hard object to see if the scraped area is a copper color or shiny silver. If the color is ...