There is a bit of confusion about amber. You will see a lot of terms bandied about – natural, clarified, pressed, natural and clarified, and so on. What do they mean and how do you know what you are buying?
Let’s start with defining what amber is. Amber is a resin which has seeped out of trees and run down the trunk. It has hardened over millions of years. As the resin has begun to harden, it has picked up dirt and plant matter from the trunk and from the wind and this debris has remained stuck in the amber. It has also attracted small insects that have been unable to extricate themselves. Natural amber usually contains small air bubbles. Most amber comes from the Baltic region, the Dominican Republic. and Mexico. It can range from being transparent to opaque and while we think of it as being a honey yellow or dark honey colour, it can be cream through to dark brown and black.
Burmite is amber from Burma which was mined between 1898 to 1941. An attempt to re-start mining started in 1999. It is a red colour and is extremely rare.
Young amber, that is, resin that may only be a few 100 years old but can be up to 30,000 years old, is called copal. It comes mainly from subtropical areas like Brazil and the Dominican Republic but also from New Zealand, Madagascar and Japan. It is also mainly a pale yellow colour although New Zealand copal or kauri is darker. Copal is softer than amber and can show white crazing.
Much of the amber for sale has been treated in some way. The main treatment is clarification to make the amber look more transparent and to reduce internal bubbles. The amber beads are placed in oil, such as canola or linseed, which is slowly heated. The oil seeps into internal fissures and bubbles. The oil is just as slowly cooled but this cooling process can lead to internal circular fractures which are called ‘sun spangles’. These look like nasturtium leaves or lily pads. So the presence of sun spangles in amber means it has been clarified. It is natural but clarified amber.
Amber can also be pressed. One form of pressing is when small pieces of amber are heated and then pressed together to form new shapes, often beads. Another way of pressing is using amber powder and melting it, pressing it, and then extruding it. This form of pressed amber is also called ‘ambroid’ or ‘amberoid’. A lot of antique and vintage amber bead necklaces are pressed amber as in the necklace pictured below. Another form of pressed amber is ‘polybern’ in which amber chips are mixed with synthetic polymer and dyed, then pressed.
Amber can also be dyed, with red a popular colour.
There are a number of artificial versions of amber, with bakelite being one of the most successful versions, together with glass and plastic. Some of the glass and plastic versions may contain imitation ‘sun spangles’. as well, some of the imitation amber also contain perfect insect specimens.