a) That's why they are a specialist. They are trained in the techniques to differentiate the fossil structure from the surrounding matrix (to the best of their ability). One of the biggest differences is texture; bone is very porous relative to most rock. Under a microscope that difference is much more apparent. You can also lick it because the porous texture of fossil sticks to your tongue more than the surrounding rock, but I doubt he did that.

b) Thats also why it took 7000 hours to do. It's really fucking hard, and he wanted to get it as right as possible. That means going very slow, taking a lot of care, and not taking shortcuts to put sculpting into play.

> That means going very slow, taking a lot of care, and not taking shortcuts to put sculpting into play.

And licking it, it seems :)

How many licks to be licked to perfection ? :p

It normally isn't that hard. The rock and fossil parts look very different. Go to anyplace where you are allowed to take fossil rocks and do it yourself. It isn't hard to visually see where the rock (limestone ends and the fossil starts. Any 3rd grader can do a reasonable job of separating rock from fossil. There are parks like that all over - most fossils are just another clam (or similar sea creature) of the same type experts have seen millions (billions?) of and so there is nothing interesting left to discover.

Note, do not let the above take away the work experts do. While a 8 year old can do it, those are the easy cases, and a few "hammer slips" don't matter. There is a level of detail that trained hands can do better. There are many types of rocks that can hold fossils, and not all are easy as limestone to work with (limestone is the majority though).

> so there is nothing interesting left to discover

Not true (see OP!), but the odds of finding something interesting are very small.