Even a novice amber buyer can perform some simple tests as outlined in other e bay amber guides, Baltic amber is much harder than Copal due to the vast age difference between them in some cases upwards of 40 million years, most true Baltic Amber is milky and pale under the crust. The warm "amber" colour occurs first after it has been exposed to oxygen for about a hundred years, jewelery producers can manipulate the Amber using heat and nitrogen to get the warm brown-reddish amber colour, which often also includes discs, called sunspangles,
Copal Amber, is a much younger amber and still retains most of its oils, as a result Copal is much softer and more brittle, and does not polish up as well as Baltic does, and when heated smells like fresh resin, Baltic Amber has more of an incense smell (Borneo Amber has a much sweeter scent), Copal is usually transparent in a champagne colour, and can vary in age from a couple of thousand years to one million years.
One final point regarding your Amber, it will not last forever, and over time will develop a thin crust due to oxygen ( Some Ambers from the Dominican Republic have crusts already after 10-20 years), It is possible to polish it, but in order to help abate the ageing process, your amber should be kept away from strong sunlight, and not be worn constantly, also it should be wrapped carefully away after use, I have some polished pieces in storage that have a light coating of linseed oil.
I hope this guide is of help