Amber has a long history, it is in fact fossilised tree resin which is on average about 30-40 million years old. Often inside the amber you can find  small plants, flowers or insects that were trapped in the resin when it was still fresh and sticky and they have been preserved since.  Although  amber was said to have magical and medicinal properties and was used as a a talisman or as an ingredient to make balms and potions it is, these days,mainly used in jewelry.  You should be able to choose from a large variety of amber coming from different places in the world with slightly different colors and look depending on  the age and the type  of plant the resin originated from. The most two famous variety used in amber jewellery today are likely to be Baltic and Dominican amber. While the former is a warm yellow and quite opaque the latter is really clean and also comes in several sub-varieties including the well known blue amber. Beware of fake amber and always purchase from a well known shop or store.