I have included this section as there has been quite a few questions on removing large pieces of amber before sanding. Amber can be sawn, drilled, filed and sanded. I have had quite a few pieces in the past which have needed excess amber or copal to be cut away before starting with the rough wet and dry. As you can see in the picture below there is an inclusion within the Amber and a lot of excess Amber around the inclusion.

The lines are where I want to remove the excess, but before cutting always first skim the outside with a 320 grade wet and dry and then put in water and inspect with your loupe to make sure there are no other inclusions apart from the one that is easily seen. Some inclusions can be lighter in colour and you could cut through a better inclusion than the one you are able to see.Cutting of the Amber can easily be done by hand with a junior hacksaw and then filed. If you have trouble holding the amber , I have found double sided sticky tape on a piece of board is a great help Make sure you leave enough amber for sanding as both tools will really give the surface a really rough finish. It is possible to use a variable speed dremel type rotary tool for the initial rough sanding however you do have to wear goggles and a dust mask and you may run the risk of burning or melting the amber as well as badly chipping it if the speed is set to high.