Baltic amber is fossil resin produced by pine trees which grew in Northern Europe about 50 million years ago. The resin was washed out of the forest floor by large rivers and transported towards the sea. In the course of time the resin was transformed to amber due to processes of polymerisation and oxidation. Yes, it is expensive as a raw material.

Amber is the ONLY product of nature in the world that is classified as a gem & is NOT mineral based.

Baltic amber generally has the following characteristics;
Hardness: 2.0 - 2.5 Moh’s Scale.
Specific Gravity - 1.050 - 1.096
Refraction Index - 1.54
Melting point - 480/720^Of (250/380⁰c)