Is This Ambergris?

Ok, I have a favour to ask anyone reading this. Today while walking on the beach fossil hunting I came across what I suspect is ambergris. I took it home and have done some research but still not sure. One method I tried was heating a pin and placing it on the substance. It gave a white cloud of sweet smoke and melted as a black tar. Does anyone reading know about ambergris or someone who does. You help would be most appreciated. Below are the images.