Amber has a long history of being used for medicinal purposes. Even today there are many who use the benefits of the high levels of naturally occurring succinic acid that is found in Polish amber.
Historically, amber was controlled by the aristocracy and not available to the common folk. But today, you find bottles of amber chips with recipes for a tincture of amber on shelves in many small shops around Poland and Eastern Europe.
Chinese companies import Polish amber chips to use in their medicines. They choose Natural Baltic Amber because it is uniquely high in succinic amber content. This is significant in that amber found in the far East is more readily available to them by reason of geography, but also the market price is much lower.
But after years of use, they know the medicinal benefits of Natural Baltic Amber as compared to other amber.
Like with most alternative cures, the curative evidence is anecdotal and no firm medical evidence can be put forward to say that the benefits are what the people believe.
But after centuries of use, the belief that a dose of a Tincture of Amber has curative powers is thought to have some basis.
Here is a link to a recipe for an Old Polish Tincture Of Amber.