All my anthroposophic friends use them. They swear by them. Their babies have a whole cycle. To begin with (from birth) they wear some stone for "protection". Then a teething amber. Then (usually overlaps) something to stop them falling and help them centre their balance while they toddle.

To be honest no-one really knows how it works. It has been empirically observed to be effective, BUT none of the explanations seem to be supported by science. One theory is that th amber resin releases oils from the warmth of the skin, but amber is fossilised, and a solid resin with a melting point between 199 and 380 degrees celsius, so this seems intensly unlikely. Allopaths ascribe various curative powers to amber but i don't know how they came to their conclusions. Amber IS electronegative so it produces negative ionisation where it's touching the skin, and negative ionisation allegedly helps the body repel illnesses, though how this applies to teething i don't know.

It is harmless if you can afford it.

Bx